There are two ways to start and either is perfectly good. You can either sit down with a Buyer Broker and tell them about what you're interested in and ask them for some names of reputable lenders you could then speak to in order to get pre-qualified for a mortgage or you could look for a lender first.
Finding a good experienced Realtor is critical, here's a link as to what you should be looking for and asking when you interview Realtors. http://www.trulia.com/blog/LarryTollen/2011/09/how_do_you_choose_a_realtor
I'd suggest reading it and then clicking on the "Find an Agent" tab that's in the green bar at the top of every Trulia page and entering in the zipcode or area that your interested in.
I've also attached a link where I go into more details on how to get started below. Good Luck and Happy House Hunting.... more