Although I hate to recommend their products, check out the Razer Black Widow series. They're mechanical and backlit. They might break your budget by a little so you may have to wait for a sale or get a coupon or something.
i owned a razer black widow ultimate for a few days.
-full sized keyboard, standard layout
-cherry mx blue keyswitches are good
-good enough ergonomics
-its pretty and it matches razer mice
-absolutely zero support for usb-ps2 adapters
-glossy surface requires constant cleaning
-software must be downloaded off the internet
-not nkey rollover
i ultimately returned mine because i require keyboards to work with a usb to ps2 adapter. if it worked, i may have kept it.
search google for "hardforums mechanical keyboards" and view the informative post over there on models and features. good reading.
backlighting and mechanical keyboards is hit or miss. ultimately dont sacrifice on keyboard quality just to get pretty backlighting.
the best keyboards may cost a bit more than you plan on spending but come highly recommended from most people who use them. remember the keyboard could last you a good long time so spending a bit more all works out in the end.
unicomp customizer, best keyswitches ever made but only 2kro