I have just moved into a brick house and the wifi does not reach through the whole house, or outside. I currently have a linksys wrt54g router in the office (front of house). I would like to be able to work outside (back of house) but am not sure if a repeater, additional WAP, or a new router is the best idea. Can anyone help??
Your router is perfect to h4xx0r with DD-WRT firmware, then you can boost the signal strength and you'll be happily surfing in your backyard! This method is totally free and easy to do, simply g00gle your router and DD-WRT and you'll find a gazillion discussions.
Experimenting with channels is really no harder than logging in to the router user setup screens via your browser. If you need a refresher on that, see literature which came with router or -- download router manual from maker's website.
It's quite possible to add a second wireless router as an access point though certain adjustments have to be made -- I say router rather than dedicated access point because routers often turn up cheap secondhand (or in the garbage) as users swap ISP. Generally you have to link the routers via a cable -- though if yours and the new one both support WDS you may be able to link them by wireless.
Anything you do could potentially brick your router, but honestly it's very simple and worth trying if the device isn't giving you what you need to begin with. But, since you say your not too technical then I'd suggest getting some new high gain antennas as they'll do wonders and it's a simple screw off and on step. I've seen replacement antennas double to range of a wireless device.