Can't help with tickets, probably get them through Oklahoma St. As for tailgating, if Oklahoma State doesn't have a "tailgate venue" then I'd recomment going to the Mo (Moshofsky Center) or PK Park. The Mo is the indoor practice facility and it's converted into a sport bar on game day, it's on the West end of Autzen. On the East end PK Park (U of O baseball stadium) serves as an outdoor beer garden and great place to hang. Note: one of the unique features of Autzen is that it runs East West, most football stadiums run North South.
As for restaurants, do you have anything specific? I like Krob Krua for Thai, Tacovore for a interesting less expensive take on mexican food, Bar Perlieu if you want good food in a casual environment (food is good, prices match). Also, The Gordon Tavern, Marche, and Rye are local favorites.
Saturday is also, Saturday Market and Lane County Farmers Market, they are next to each other downtown. You can find good food, music and typical hand craft stuff.
Two things, take time to check out the U of O athletic facilities, see my profile for a pic of the track and field venue, Hayward Field. Second, check out Oregon Pinot Noir, several good wineries in the area, plus Broadway Wine will be able to head you to a nice wine to meet your taste.
As a golfer, you might check out Fidler's Green, it's probably the largest golf shop in the Pacific NW, plus good prices.wo