Suggestions on music?

Ok, so my mom brought me this £15 iTunes gift card for my birthday and I have used £4 of it to download 4 singles that I have been wanting to download to my iPod for along time. But I am now stumped on what I should download with the remaining £11, lol.

Has anyone got any suggestions on what albums or singles I should download? I usually only like mainstream stuff. My favorite genres are pop, electro-pop, rock, rap and dance.

y dont u just download 'free' songs?-.- theyre 99% same as original ones.......save money etc
n as for songs..try..umm......breathe carolina?blood on the dance floor?p!nk?brokencyde?3dg?a day to remember?30 seconds to mars?alesana?or my favez...lifehouse :D
for song names look on wikipedia for each bands latest songs n hear em on utube then get them if u like.tho u can get all of em for free >.>

I have different taste to most people. These are some bands/singers that I like.
Nirvana
David Bowie
The Doors
I could go on for ages.

Thanks for all the suggestions, I'll check out all of the artists that I haven't heard of on wikipedia and youtube.

And xJohnny, yeah, I heard you can download music for free, but I am bit skeptical of it. Basically for me, when something sounds good to be true, it usually is and I have got the feeling the free music might not have such good quality sound.

the beatles!!!!!!!!!!!!!