Be specific with the title and issue #'s you need. Do not send "Got any Spider-Man?" I have hundreds of Spidey titles in stock. I don't have a database, since my stock changes rapidly, so I have to type up each price list individually. I respond to dozens of inquiries per week, and I cannot afford to waste my time and yours typing up a list of comics you don't need.
If you are looking for multiple issues to fill in a run, list those issues.
Example: Amazing Spider-Man #129, 200-thru-210, or simply 200-210.
When I send you a price list, please reply, even if you do not intend to buy. For one thing, it is simple good manners. For another, I could use the feedback to improve my customer service.
Why are you not buying? Prices too high? Condition too low? Payment info not clear? With no response I can never hope to improve my business, so please reply.
Recently, I have been receiving Want List Inquiries that are thinly disgused pricing requests for someone's collection they are trying to sell.
Please DO NOT DO THIS!
Buy a Price Guide, or check an online Price Guide.