You could go on Twitter and find some yaoi pictures! (=・ω・=)
I use normal pattern backgrounds that remind me of different BL series. For example, yellow and white stripes remind me of Doukyuusei.
I also use screen shots of my favorite scenes. Like the ring scene of Yuri on Ice.
KyoNoZa has some amazing images in her albums. Absolutely beautiful stuff. You might want to look through her page.
Sorry, I misspelled her name. It's KyoZaNa and there's a little flower-thingy dangling behind it. Here's the link: http://www.mangago.me/home/people/2337/album/
tnx for the suggestions ლ(´ڡ`ლ)
This one is so special to me, there's no unnecessary dialog but it caught me in the feeling ლ(´ڡ`ლ)
http://www.mangago.me/home/photo/220377/
Am looking for a beautiful yaoi background for my pc i trie google but i couldn't find any that spark my interest, so i though that some of u guys may have some interesting ones doesn't hurt to ask heheheヾ(❀╹◡╹)ﾉ~