See Dynamic Web Enterprises (http://www.smallrc.com) or Bob Selman (http://users.joplin.com/~bselman/) for your actuator needs. They have a variety of sizes (and corrosponding thrusts) for you in both surface mount and remote mounted types.

They also have the receivers, batteries, motors, gears, props and kits to get you started. DWE has combo packages that have a model, radio, optional chargers and transmitters.