Transitioning from Hourly based consulting to project based...

Hello.  I've had a reasonablly successful custom software development
practice for a little over two years now.  The practice has been built
on hourly consulting engagements that are typically delivered on the
customer site and (at least partially) under their primary direction. 
These engagements have been found through some limited local marketing
and word of mouth.

I would like to begin to transition my engagement portfolio to include
some "project" based (perhaps milestone based or something else)
opportunities.  In other words, I would like to provide the outsourced
architecture/design and implementation services for custom software
projects or key components.  This outsourced development would be
primarily under our control (with appropriate interaction/coordination
with the client of course) and done on our premises, schedule, etc.

With the above in mind, I'm wondering how best to learn about such
project opportunities?  Many job boards exist, but few useful project
boards that I have found - for example ProSavvy does NOT appear to be
effective or economical at all.  How about RFPs and the like - how
does one get on the bidder's list?  Are there other such methods of
finding and bidding on projects.  Additionally, how might we be able
to convince potential customers to go with us over larger companies
with many more projects under their belts?  I'd welcome any and all
suggestions and discussions on this topic.