I have been visiting this site nearly everyday for a few months now gathering up ideas, so let me start by saying THANK YOU to everyone here for giving us all the great ideas to get started in this wacky hobby! Having said that, my situation is a little different, so the screen that I have built is different then most of the screens here. Hopefully it will help someone else who is looking at getting started!
The main obstacle that I had to overcome was my ancient projector. I was given an old CRT projector and although the picture isn't too bad, it really isn't the type of thing that you can drag out into the backyard for a 90 minute movie and then drag back inside. Not only is it VERY heavy, but it is also very finicky and has about 30 different pots to adjust about 30 different areas of the screen...it can take hours to get just right, but if it's moved from that perfect position then you might as well start over. It's not ideal...but I made it work.
So here's what I came up with:
It's an 8ft x 6ft frame made out of PT 2x4s and spray painted flat black. The back of the frame has velcro glued and stapled to it and I have a Queen sized bed sheet with the matching velcro sewed to it (not that easy to sew velcro!!!) I've buried 2, 2ft lengths of 1" pipe in the ground (if this works out well, I'll cement them in next year) and I have a 1/2" pipe attached to the wooden frame using a bunch of brackets I picked up at the hardware store(s).
It's kind of hard to describe but basically I have it so I can just lay the frame on the ground, slide the poles into the brackets, lift the frame upright, and attach the screen. I also have guy wires for the front and back but I haven't had to attach them yet. The whole process takes less then 5 minutes from getting the frame (stored above the garage door) to being ready for a show in the backyard. So I'm very happy about that.
As for the projector, that stays inside and shoots through a bedroom window and projects in 'reverse' mode onto the screen which stays in the same location every time thanks to the buried pipes. The sound then runs through the wall (I received special permission from my wife to drill a hole in the outside wall) and from there goes to 2 small outdoor speakers that attach to the front of the screen.
Sorry about the wordy post but I didn't know how to explain it all in less words. Please feel free to ask specific questions if I wasn't clear enough! Thanks again for the ideas!!