Welcome to the forum Mike! Glad to have you with us! A few things we would like you to do. Please add your location so we know what area you live in. It helps on what advice we give. Also, since you are new to smoking, take Jeff's free 5 day e-course. Lots of good info there. Don't forget the seach bar. It will give you lot's of help. Other thaqn that, ask questions. Plenty helpfull people here.
Now for your questions:
For spare ribs check the 3-2-1 method. Baby backs a 2-2-1 method. 3 (or 2 ) with smoke, 2 wrapped in foil, 1 with heat. For ribs, use a rub you like and usually about 240 degree smoker temp. Use a thermometer that has been tested for accuracy to determine the grate temp.
Also, practice with a rack or two before the party just to get a good feel for what you are doing! I'm sure you will have more questions after that. Bring them on!