Myself and a group of guys are considering taking a walleye charter and I had a few questions as I havn't previously fished the lake.  Whats the best month/time frame to go , what charter have you used and would you recommend, what is a fair price, and how many guys should I try to get together to go? Thanks!

Many charters offer passenger room for up to 6, but I (personally) would stay at 4 unless it is one of the bigger boats. Ask the captain you are wanting to go with what they recommend as the most comfortable fishing numbers for their particular boat.
 
Prices range from around 550 and up a bit, some slightly more, some less. Much depends on the size of boat and type of charter... walleye and perch, just walleye, just perch, full day/half day, etc...
 
Best time of year will greatly depend on location you are looking.... the western basin of the lake (mosty from Pa line through Ohio) is hopping from early spring, but the far east (such as out of North East) generally isn't as dependable till mid to late summer, depending on weather.
 
The captains are good for giving you information to help you decide what works best for you... don't be afraid to ask them since they know their own areas better than anyone else would.
 
Have fun!

Thanks!

Mid June-late August. Some boats I know first handedly are good at what they do are Eye Crosser, Reel Obsession, Wolfman, Gypsy Lynn, or Buckets.  All are docked in East Canal basin in front of Hamot Hospital.  All are very good boats and real experienced captains. Prices range for each boat. PM for phone numbers for each guy.

Went for lake trout with Buckets last year.  Top notch!  Does even better for Walleye from what I've heard.