once you are logged into the DIS, you should be able to see the rent/trade board in the
DVC section.
first thing to be aware of is that DVC owners can book 11 months out at their home resort and many do...so availability 2-3 months out can definitely be spotty and some owners won't even bother responding to you for short notice requests since those requests are often a waste of time.
but if you are flexible and willing to consider larger resorts like SSR or OKW, there may still be availability. if you expect to book smaller resorts like BLT or BCV, you will probably be disappointed unless you start looking about a year in advance (although it is true that anything can happen - it's just more rare to find something 2-3 months out.)
also, it's getting a little dated but you should definitely scan through the [thread=1669863]
Considering Renting from a DVC Member?[/thread] thread...
one thing that has changed from that thread is that renters can verify their reservation directly with disney now on this website:
http://mydisneyreservation.com/DVC
but you are dealing with an individual and not disney, so understand that you may not have any option to cancel the reservation and if disney offers "free dining" or "40% off" deals, that would not apply to you as a DVC renter.
also, DVC reservations are timeshare stays so you also do not get daily housekeeping...more like some form of housekeeping every 4 days.
edited to add: you can rent stays at DVC resorts directly from disney - and get daily housekeeping - but the costs would likely be higher than on a points stay.