J.M.
Hi A.-
You've received a lot of advice already, but I will try to offer up some new ideas. I'm not certain where you are located, but an absolute LIFELINE for me as a Mom has been my MOMS Club. You can find a local chapter at: http://www.momsclub.org/join.html or, if you happen to be in zip codes 92647 or 49, you could join ours, the MOMS Club of Huntington Beach, North. Most MOMS clubs have several playdates or outings a week, and you can be as busy as you want to be. I've done them here in the OC and in Northern CA from the time my oldest (now 3 1/2) was 2 mo. It was great for me to meet other Moms to connect w/, and the kids play together, so you do get a break.
There are so many resources and free things to do in this area as well, some mentioned library storytime, etc. and maybe if you think of your week like a preschool/daycare time, then your son would be engaged & excited too about all the activities, i.e., Mon. we go to the park, Tues. is storytime at the library, Wed., etc....
Finally, another group I discovered last year that truly is JUST "me time" is MOPS International. http://www.mops.org/
Most MOPS groups meet once a week, childcare is part of the program fee, so the kids are cared for while you enjoy brunch, getting to know other moms kid-free (no one tugging on your leg repeatedly!), hear a speaker, sometimes do a craft--I love it, and have made some wonderful girlfriends through this group.
Overall, I would encourage you to get creative on your own first...but if you still want to try a daycare/preschool type program, see if there's a school that would let you try it out 1 day a week & see how you both do. If it's great and you're both loving it, go to 2 days. My philosophy is that they have their whole lives to be in school, and unless you have to start them young (for work, etc)., try to see what local resources there might be that would engage him, give you a break, and I bet you'll both be happy.
All the best & good luck!
Jenny
(Sorry this was so long, guess I had a lot to say! :)