I take it the person you bought these from didn't know the brand either... that's a little scary, but on the flip side, you may have scored some decent rims for cheap.
I've looked through several rims catalogs that I have, and they may be (or not) an inexpensive knock-off of either an Ultra Wheel or a Pro-Comp Alloys rim. They offer rims that are very close to what you have.
That logo may be unique to the center cap. Most rims do not come with any center caps... as they are extra $$$. The original purchaser of the rims may just have picked out some caps that were at the parts store.
Sorry I couldn't nail down an exact brand... and of course, I may also be 100% incorrect.
