Recently I prepared 26 free hdri maps for all community members, You can use them in Maya of course also in commercial projects but please do not redistribute them on your website or with your Maya projects, it took a lot of job to prepare them. Anyway I share them for free.
I had to limit somehow direct downloading so you have to register (it's safe, please use valid email. if you don't wish newsletter uncheck it).

If you encountered any problems with download please PM.

Get free hdri maps

I would be glad to see some projects created with this maps and Maya, you can post it here.
Enjoy it!