Hi Todd,
There are two ways to get into
DVC.
One is to buy direct from Disney, which is the process you have already started. They are currently selling Saratoga Springs primarily, but you can also buy points at the sold-out resorts through them, subject to availability. With the Saratoga incentives, I believe their discounted price right now is $87 per point. Rumor has it prices will increase slightly in June. Points at sold-out resorts are $89 and there are no incentives. Buying from Disney, you must buy a minimum of a 150 point contract to start. Once you own a DVC contract, you can add on later from Disney in increments as small as 25 points (50 if you want to finance).
The purchasing process is quick and easy through Disney, and they offer financing.
The other way to get in is resale. Click on the Frequently Asked Questions and DVC Resales links at the top of this page and you will get the basic resale info. Resale contracts are sometimes smaller than 150 points, and resale prices tend to be somewhat lower than buying from Disney, depending on resort.
The purchasing process through resale is fairly long and can be very frustrating. Disney has the Right of First Refusal on all resale contracts, so you could make a deal with a seller and have Disney snatch it away from you. Sellers also back out at the last minute occasionally. Also, with resale, you have to get your own financing. You also usually have to pay closing costs (not a trivial number) with resale, but not if you buy direct from Disney.
There is a difference between Saratoga Springs and the sold-out resorts (regardless of who you buy them through) that you should be aware of. Saratoga Springs expires in 2054 - 49 years of points. All of the other resorts expire in 2042 - 37 years of points. If you do the math, you see that there is really not much difference in the true price. The sold out resorts cost less resale, but the duration of the contracts is shorter. Saratoga Springs costs more initially, but you are getting 32% more.
Some would argue that the extra 12 years don't make any difference if you only plan to keep the contract 12-15 years, but I disagree. I believe that fifteen years from now, a Saratoga contract with 34 years remaining will be worth considerably more than one of the other resorts with only 22 years remaining, because that buyer will be looking closely at
their resale opportunities.
If you are looking to get in for a lower price, you can definitely do that with resale, but research the deals and the process closely before you do. I bought resale, and many, many others have. You will save some money, but you need to know what you are doing. Reading everything you can find here involving resales and/or ROFR (right of first refusal) is a good place to start. Unfortunately, you will find that the info tends to be scattered around quite a bit, so you have to really search for it.
Good luck.
We have added on 5 times so valeriekc is correct. You never have enough. We go to WDW every year but have traded several times to other locations. Some locations will be hard to get but others are quite simple. You need to consider the expense along with your needs in the future when buying points. You didn't say have many in your family or their ages. Children get bigger and the needs get greater. I would go for as many as you can now because we joined in 1994 and the prices have gone up-up-up. Remember to buy enough for that trade if that is what you want. I believe a week trade starts at 160 in a studio but I may be wrong. Good luck with your decision. Have you stayed at a 
