This review is short, but it does what it says on the tin, I can't possibly write an essay about the subject!
There are 3 main video games stores in Blackpool, as well as other shops which do sell them.
The high street games-store as found in most shopping areas can also be found within the Houndshill Centre of Blackpool. Staff are usually friendly types here, not the sort of geeks you tend to get in Games Stores. There are 4-5 demo games you can play, however these are usually taken up by 6 year olds who can barely reach the controller. If you're sad enough to care about playing on a game in store I don't know what to suggest other than just getting their early- or offering sweets to child as bribery. To be honest I wouldn't suggest you do either. The store is well lit, with 2 or 3 crates filled with old, used games all going for as little as £2. It's possible to trade in your games here, however you will probably not get as much as you can from Eclipse. For example, the game Fifa 2007 would get you £5 here at Game, where as at Eclipse you could get up to £8.
Another high street chain of games store found within Blackpool is Gamestation, on the alleyway like Corporation Street. The shop here is very small, and badly lit, not too dissimilar to a teenager's bedroom. It's also very crowded with all the things they fill it up with, and the amount of people who visit it. Similar to Game there are 2-3 demo games available to play, but you're more likely to find a geeky 13 year old playing on here, rather than a 6 year old as with Game. To prize these sorts off them you could offer them a free pen or something. Price wise it's probably the highest, and there are fewer older games going on the cheap here. Not the best.
An independent store (now has branches in Clevelys, Preston) is 'Eclipse Home Entertainment' found on Beech Avenue near Stanley Park (about 2 miles from the town centre). The store is fantastic for old games with its large selection of traded in games, all going for low prices. The staff are also better here, usually older (30+). This tends to make them better at serving the customer, and more helpful. Another upside to this store is that its usually very quiet, with no more than 3 people in it at a time. This combined with the fact its quite a large store means you can glide around easily enough.
My Tip- Eclipse! Its new games may be a little expensive but there more than made up for with the older games which are always cheap. The shopping experience is second to none, with good staff, a large (ish) store, and the fact its never busy. Go there if you need some computer love.