For the girl bday party id say something like a baby doll w accessories.
Play food w a grocery cart.
Big chunky books.
A snack basket? My guys love the cereal puffs and yogurt melts.

baby doll it is! Thanks Ladies :)

Larger cars/trucks to vroom around the house and yard, the bubble popping lawn mower, sit-n-spin, see-n-say, coloring books and learn to color crayons

DS just turned two, so for his birthday we got him a couple new books, a duvet, an Octonauts duvet cover and pillowcase set, a new pillow for his bed, a box of lego duplo, crayola wonder markers and a matching coloring book, some new shoes and a pair of rain boots. He loves everything we got him, surprisingly!

My son is going to be 3. He was not yet into cars but I got him some anyways and I am glad I did since he loves them. You can get him a fire truck toy for around 15-20 dollars at a store that makes souns, and the ladder moves around. I got my son a train table last year, he uses it. I did put up the tracks and such for a later time and hes just uses it for driing his regular cars around. Also puzzles are fun they have some cute puzzles out now that have pegs for little ones. I also found that the new crayola sets are awesome. They have markers and pens that dont make messes, just use water, or like a magic marker. I also got my son last year a set of crayons that he can draw on the bathtub walla which he loves. He will play with them and we color together, you just wipe with a washrag and it comes right off wth water. Maybe those newpillows that have built in led lights. My son is obsessed with cars but Step2 came out with a new car bed. It actually has lights that turn off and on with touch, fits a twin bed, and looks just like a brand new corvett. I am getting this for my son, it also fits a toddler mattress too, and has race tracks inside. Also if you have a large area for play in your home, or outside, they now have roller coasters for kids at home. Its a ramp with a little buggie looks like a blast. Every child if different. Some are more active and adventrous, and some prefer more mellow play. Kids love those sand boxes, or water tables as well. I hope this helps I dont know too much about you or your son but construction vehicles are good, as well as those little sit and ride toys that he pushes with his feet, they have lights, and sounds, and such. Best of luck and good for you to prepare. I have to do this with my son too since he is exactly one month from x mas since he is a nov baby so I go all out for his b day . I like to be done before nov even comes. :) I search amazon, and then check e bay for similar toys that may be cheaper, or walmart. Just search toddler toys. :)