I read that boys are drawn to toys and activities that are about motion. This was certainly true for my son. We got him a train table from Craigslist and a couple of train sets from Ikea and Melissa & Doug and 2 years later he still can play for hours around that thing. Also boys are drawn to spatially oriented toys, and at this age they like to practice sorting. So my son loved the wooden blocks that he could build with and sort by shape. He's never been much interested in art, sadly. Maybe someday. I get a little tired of the cars/trains play, so I let him do that by himself and I jumped in a little here and there. We love reading together and we do that a lot.
I'd also suggest as much time outside as that is really fantastic for building up your little guy's brain. For me it's easier to talk about things happening in nature and see what he's observing. Waldorf education is really big on nature inspired learning and developmentally appropriate play so maybe there's a book from the library to check out that can give you ideas.
The other thing I'd check out is activities at libraries and other publicly funded institutions like your parks and recreation facilities. Our libraries in Portland have something every day for every age group (at different libraries).
Also at this age he might love to help you do things around the house. It means everything takes longer, but it's also an activity for him and he will get good at it. He can bring napkins to the table, and maybe set his own place, he can sort socks in the laundry, he can pick up his toys. I made a spray bottle with diluted Dr. Bronner's soap so that my son could spray things and wipe them wiht a rag like I was doing - - I just let him spray/wipe randomly.
Our son never watches regular TV and we watch about 1 very tame dvd a month (he's almost 4) as "movie night." I kept him away from anything like that till he was almost 3. As a result he's very good at playing by himself and with others and has a fantastic attention span (better than my husband), great imagination, curiosity, is really well behaved and mimics the books we read for role play instead of commercial characters who don't display behavior I feel comfortable with. Kids don't need any TV, and I felt the longer I could put it off the better. I know when he's older he may be more insistent about asking for it, so I just wanted to build up his play skills without it.
Best wishes! I wish I could work at home with my kids, good for you!