Its definately worth it for a couple of pounds, as it does work for some flavours.
If you are going down the DIY route, here is a decent beginners guide for you to peruse
http://allaboute-cigarettes.proboards.com/thread/21122/beginners-guide-mixing?page=1&scrollTo=393373
But all i usually do is find a recipe on what i think i would like, then using the ejuicemeup calculator, put in the desired percentages etc.. which tells you how much of each ingrediant is needed and put them into a bottle and wait

Its really very easy.
Loads of recipes here
http://allaboute-cigarettes.proboards.com/board/40/recipes
Then buy some Nic base, PG and VG and flavourings.
I get nic base here at vapers emporium
http://vapersemporium.co.uk/index.php?id_product=29&controller=product&id_lang=2
If you vape at 12mg, then 250ml of 72mg is enough to make nearly 1100ml of juice lol, which at 3ml per day will last you exactly 1 year lol.
PG and VG can be bought from classikool off the Bay or VG can be bought in boots.
Best range of flavours imo is chefs vapour site, it does capella, PA, t-juice etc...
Cheers for that, great info as usual on here!
Well, I've still got more premixed to try out first. Just ordered these 1ml samples from smoke rainbow:
BumbleBee, Lemon Refresher
BumbleBee, Malt Toffee
BumbleBee, Strawberry Conserve
Mt Baker Vapor, Cinnamon Roll
Mt Baker Vapor, Johnny Chimpo
SteamGunk, Captain Custard
SteamGunk, Snickerdoodle
T-Juice, Colonel Custard
T-Juice, Jack The Ripple
T-Juice, Quintessence
Trip Hammer, Fruit Pastilles
Trip Hammer, Lemon drizzle cake
Trip Hammer, Christmas Pudding
Trip Hammer, Fizzy Trifle
Trip Hammer, Fruit Salad
Trip Hammer, Puros Santa Clara
Trip Hammer, Rhubarb & Custard
Trip Hammer, Tigers Stripe
Trip Hammer, Toffee apple
Trip Hammer, Tripavanna
Trip Hammer, Tripperbocker Glory
Trip Hammer, Victoria Sponge