want to start lifting--cant afford gym membership

I think the decision to incorporate some weight training into your fitness program is a good one. You rock! You're right in that it is important - for many reasons (not just building muscle). I hope you find it to be beneficial and fun.

I don't have any familiarity with programs likeP90X, but I think getting started with some kind of program will have benefit. When I first started lifting weights, it was just to get back the muscle I had lost through a calorie-deficit diet. I worked up a sweat moving 5, 8, and 10 lbs. dumbbells around in combination exercises that worked all of the major muscle groups, just twice a week. Within a couple months, I was already seeing results. (I just wish I had taken pictures beforehand).

Here's a pretty good beginning program that you could do with some free weights, that was pretty similar to how I got started.
http://www.muscleandstrength.com/workouts/dumbbell-only-home-or-gym-fullbody-workout.html

But like I said, I think any program that emphasizes resistance training will be of benefit for those just starting to get into it. Over time, you'll want to increase the intensity by adding more weight, sets, and/or reps. And you can check in here periodically and let us know how you're progressing and solicit ideas for ways to help increase that intensity. There may be some groups here that are doing the same thing as what you're doing.

Best of luck to you! And don't forget to take progress pictures!

just start lifting those free weights.

watch some youtube tutorials or if you have cable, there is TONS of free ondemand fitness workouts, its such an untapped resource

make sure you take it slow, and have proper form, get a cheap long mirror from target or something, and watch yourself lift, and watch yourself change

lifting weights saved my life.

i wish i had free weights at home, you are a lucky lady

tons of great smart phone apps with built in weight training routines for beginners.

P90X seems like a quick fix.

The people I know who do it. Have to keep going back to it.

For me that's just not sustainable.

Not sure I understand what you are asking. You stated that you have dumbells but didn't specify the weight. If you plan on buying dumbbells, plan on spending $1/lb for each dumbbell. Due to the cost, many choose to join a gym. I know you stated that joining a gym was too expensive but If you decide to buy dumbbells, I recommend buying a set of 8s, 10s, 12s, 15s, 20s, and 25s, along with either a bench or exercise ball. That should be enough to get you started. The weights will cost about $190 (new), the exercise ball should be around $70 (buy a higher quality burst resistant one), or a bench which will cost between $45-90.

My husband purchased the dumbells to complete the series when he did it about 6 yrs ago. So I have 3lbs-5lbs-8lbs-10lbs-15lbs-25lbs and 35lbs. I also have the resistant bands that are multi-colored so you can change up the weight resistance. I do have a great quality exercise ball at home too. The only thing I don't have is a bar to do pull ups. I am sure I can figure something out with that though.
I am just nervous about how overwhelming it seems at first. I also know I will need to up my calories and protein but I am still trying to figure out what my correct TDEE is.

My sweet hubby is buying me a fitbit this weekend to help me figure it out though. I am nervous/excited!

For free pull up bars: do you live near a park with monkey bars? The free weight increments you have will be great for you! And I LOVE resistance bands. Just youtube different excercised you can do with them, it'll help.