Before you ask anything about my dress ups, please see if your question has already been answered in the F.A.Q. Thank you.
Just when I was about to upload my K-on! game KawaiiPandah uploaded hers. What a coincidence! Though hers is better...
To tell the truth I don't even like K-on, it's cuteness and moe moe are way too forced for me. And actually I only like Ritsu and Tsumugi, while the rest of the cast (especially Yui) really gets on my nerves with their "I'm cute and adorable and moe don't you want to hug me now go and buy all the merchandice that's related to meeeee^__^<3<3<3". But I thought excluding 60% of the characters wouldn't be a good idea, and they have nice outfits, so have yer Mio, Yui and Azusa as well.
I know this is a really dumb place to put this question, but have you heard of the Idolm@ster games/music? Or, in a similar vein, School Idol Project? Seeing the K-ON dress up of yours I was reminded of them. However, I'm not quite sure of what types of anime or manga you like, so I'm pretty sure I'm taking a wild guess here, haha...
With both, they focus around Idols (Idolm@ster focuses from ages 11-24, School Idol is 15-17), but IM@S is more unique and digs rather deep with their characters. TVTropes does better with explaining than I do, if you don't mind skimming through.
Here's Idolm@ster: [link] School Idol Project: [link]
Here's Idolm@ster: [link]
School Idol Project: [link]