There is a misconception that once you get an agent things will start to snowball from there and you'll be on the fast track to success. That is unfortunately a myth. The reality of it is, the road is long and hard even after you get an agent. You move on from having to impress one person, to having to impress an entire publishing house. Publishers do not buy books lightly, especially not with the tumultuous state the economy is in.
I had an agent and believed the myth myself once. After a year I ended up parting ways with him due to a restructuring of his company. Do over night successes still happen? Yes, but they are fewer and farther between today.
You will go through at least one edit with your agent to polish up your manuscript. This process can be quick or painfully long, it all depends on you and your work. The faster and better you edit, the faster this part of the process will go. My edits took about a month, between me doing them, e-mailing them to my agent, and him approving them. Once he was happy with the work he began submitting me immediately.
After you get an agent the work does not end there. While they're working hard to sell your book you need to be working hard to sell yourself. Your online presence will become vital. Editors looking at your book will most likely google you to see what your platform (or online presence) looks like. Always be careful what you say. Be careful what you say on line. If you don't want a publishing house editor who's considering buying your book to read something you said on line, you shouldn't have said it. Help your agent sell your book by maintaining a professional on line presence.
So how long does the process take from agent to publishing contract? I'll let you know when I get there! It's different for everyone. If you remove time for the holidays my book has been on submission for going on nine weeks now. The great news is, we haven't received a single rejection yet! The bad news, I've realized I really need to work on that elusive virtue called patience.