I am hoping to move shortly to the Barcelona area. I am Photographer by trade but was wondering is there much demand for photography in Spain. Thoughts and feedback appreciated.

You don't say whether you speak Spanish, or more importantly Catalan, but without either I think you'd be struggling. As a keen amateur tog I read the photographic forums and even in UK every man and his dog fancies setting himself up as a photographer. Never sure why? And it's no different in Spain. Reading the Spanish photographic forums as well it seems to me that the situation in Spain is exactly the same, loads of wannabees all trying to become pro togs. I think unless you are world class, have something special to offer, you're really going to struggle. If you do read Spanish you can try any of the below, ask a few questions, she what the locals think. ¡Ojalá que tengas suerte!
http://www.fotopopular.com/smf2/index.php
http://www.forodefotografos.com/
http://www.caborian.com/foro/

I can only tell you about around here, being the member of a couple of photographic groups.

I know of two Brits who run "businesses" as photographers. One works for an estate agent and the other as a freelance just taking what comes. He does calendars, promotions for restaurants .. that sort of stuff. Neither of them speak "workable" Spanish as far as I know.

The number of people I have come across that think they are fantastic photographers and could run their own business here is quite large ... the number that have actually done it as far as I know is none.

Agree, there´s no shortage of "good" photographers, but not so many earning a decent living from it. Nearly everyone with a DSLR fancies themselves nowadays, especially the "weekend warriors" doing a few weddings here and there, undercutting the big boys. I think the word "pro" is used too easily nowadays, it can mean anyone that has sold a few photos! I take my hat of to the real pro´s, they´ve served their time and it shows. I think a lot of the Spanish would be reluctant to forsake their normal local photographer, that has been doing all the family communion, wedding shots for years, for a guiri! If the OP is good perhaps he´ll make a go of it, but I would have reservations about his chances of success.

An enthusiastic amateur.

I've got to tell you, I've done weddings back in the pre digital days, and it aint much fun! I guess wedding photographers must get hardened to it, but sometimes you feel like punching the guests

I´ve done two as the sole photographer, (turned down many more) complete with Blurb wedding albums, but only because they were family and I couldn´t get out of it! I can think of little I´d least want to do as a way of earning a living. In fact, I´d hate to be a full time pro, photographing people´s kids, cheesy glamour shots, boring product shots etc. Like you, I guess, I go where I want, when I want and photograph what I want. Just done a 30"x20" canvas for somebody,and am awaiting the delivery of the same size print done on aluminum. Very expensive the aluminum, (over £200!) but it looks impressive.

I would imagine having spent time setting up the group shots and then having all the guests taking your setup would be very annoying - especially when they impede your work
There can only be the one "big day" and if for whatever reasons it is spoilt by poor photos, dodgy video etc etc it cannot be recovered.

IMHO the op shouldn't be moving to Barca and then thinking about being a photog - he should be moving because he is a photog who is getting plenty of work there.

well he didn't say he actually punched the guests........................

Can we see it?

I didn't actually see it myself! I always have prints delivered to me to check out first, but there was delay, and whereas a print cost a £1 or so to send on, a large canvas costs £10! So it went straight to the customer, and she's pleased, so it worked out OK. The photo itself was just a local village, not one I would have chosen, but seems the customer came from there years ago. This is the aluminum mount I have used, http://www.anneherbert.com/page.php?pageid=16 It's actually destined for a bathroom, so will withstand condensation etc.

I was being curious for the foto´s you make, I always enjoy to see other peoples foto´s. Well, not their familyalbums.

Works both ways.... my #1 son asked me to make sure I had my camera to catch the more spontaneous stuff the pro wasn't doing on his big day at the end of June; I'd got a great thing going with son & his (since primary days) schoolmates who all know me, they were ar$ing about as only young men can, I was getting great stuff and then, out of left field, I spotted the pro hoving into view & proceed to take over my setup!!!!

A good pro takes several shots ... one for the stiff formal picture, and once he has taken it, takes a few more as people relax. The guy I knew in the UK won the Fuji Film wedding photographer of the year by doing just that and getting some tremendously relaxed and natural shots

Yes I've had the very same thing happen to me, it's irritating isn't it?

I worked for over 4 years as an advertising, fashion and editorial photographer in Barcelona (though over 10 years ago), but I think some things are probably still relevant today.
You will be needing 1. an agent (as you may not speak Catalan) and 2. a means to make invoices with a tax number (otherwise no chance of being paid). When I moved there, Spain/Barca was keen to be seen as "worldly" and so clients were happy to employ a foreigner. Now you'll find things very different. Unless you can bring something totally new and fresh to the table, there is little chance of any real work. Also keep in mind that agencies are now taking over a year to settle invoices, so you'll be needing deep pockets to keep cash flow alive.
Your best bet is to come over on holiday with your book/portfolio and then hit the phone. Most picture editors speak English and are pretty approachable. And in the meantime you can be checking out studios for hire.
Good luck!