I too have had good success with mortgage brokers and there is no obligation or (usually) cost for you to get an idea of what you would qualify for. As for your credit, I think it is a good idea to personally be aware of your credit situation and score and the best way I know how to do this is with http://www.FreeCreditReport.com.
They provide a free trial subscription and you get your score and report from one agency and then if you want more detail you can choose to pay for a more detailed report.
If you want more information, please feel free to contact me and I can refer you to a good mortgage broker and/or real estate professional in your area if you like.
Visit my website at: http://www.TimDenboHomes.com
Best of luck!