Going to Cairo...need some advice

I plan a short trip to Cairo next week (never been there). Want to do the shops on Muhammed Ali Street, maybe visit Maurice. I would like to find some antique instruments, riqs, ouds, etc. Any advice? How not to get seriously ripped off? I don't speak Arabic. Also, how do I get to see the great Mr. Shehata? Does he have stuff in stock usually?

Thanks in advance. Also, where should I go for live music?(oud of course).