Santander Central Hispano bought Abbey National a year or so ago. There are banks such as Barclays which have branches here but normally only in the major cities - i.e. there is one in Barcelona. You might find that this is irrelevant however as group companies such as Direct Line and ING operate in both countries but don't interchange information so it's pretty irrelevant if you have a UK account and want a Spanish one.

Personally I haven't had any problems obtaining credit here (I'm not a credit person but a credit card is useful, as are trade accounts). I've been checked by Mapfre (who secure a lot of the credits here) and so far no problem.

It might be that you are worrying over something that isn't a problem.

Nigel