A foundation primer is your new best friend! It prevents more oil coming through, keeps skin even, stops the foundation soaking into the skin and looking patchy and tends to contain calming ingredients that soothe.
Nars does one (a bit pricey, but excellent!) and Ruby & Millie used to have one too that was much less expensive. Mac does a great product called Prep + Prime which does much the same thing too. I also really like their foundations which come in about 12 finishes and a billion colours and start at about �11 a bottle, which is quite a reasonable price!
Often though its not the wearing of the foundation giving you spots, but not removing it well enough! Never ever sleep in your make-up ( that's the best piece of advice I can give you as a make-up artist who gets spots!) and use a good creamy cleanser to shift it all off last thing!