Good morning...
Frankly, 3 pound weights aren't going to cut it. The interesting thing about muscle growth is that to make any progress you have to keep challenging the muscles. You will grow out of 3 pound weights VERY QUICKLY. (and don't worry about 'getting too big' or 'too muscular' - unless you have a TON of testosterone or are taking steroids, it ain't gonna happen).
It's difficult to recommend a weight for beginners - as everyone is different - that's why Bill Phillips doesn't recommend an amount of weight to lift in the book. Basic rule of thumb: if you can do more than 12-15 reps, it's time to move the amount of weight up. You want to EXHAUST the muscle - because muscles don't grow during the lifting process but rather during the recovery process!
Now, I belong to a gym and love it - my apartment is very small so I don't have the room to have weights, etc. Besides, I get a charge from working out with others...I know Susanje and a couple of other folks here do work out at home. If I was going to work out at home, I would buy a good bench and a set of PowerBlocks (see
www.powerblocks.com for more info).
I would recommend checking out the gyms in your area and pricing them - see if you can get a free pass for a few days or a week and give it a whirl. Many gyms - especially the chains - tend to run lots of specials. I only pay $24 a month for my gym membership!
If you can't afford a gym or additional weights, I'd suggest checking your local community college. Many of them have really nice equipment that you can use just by coming in or signing up for a physical education class! Definitely worth a look see.
I do encourage you to read the Krista Smash website (link at the "Basic BFL Info" at the top of this forum) for some really great info for women beginners (along with the BFL book of course). Basically though, 3 pound weights aren't going to cut it.