For the cheese and garlic it would be easier if you got yourself a cold smoke generator, though you can do without. The requirement is to produce a good supply of clean smoke without producing significant heat. Some do this using smoldering sawdust in a tray but a more controlled way is to use something like an AMNPS or a ProQ cold smoke generator
I have both and I find the AMNPS much more effective than the ProQ. If you would like to try either one out then let me know (and no, I don't sell either of them )
Once you have the smoke sorted then it is down to the things you are going to smoke...
Cheese - When you get going try a variety of cheeses, but to begin with simply get some supermarket own mature Cheddar and cut into chinks about 2cm thick. Spread these out in the smoker and leave to smoke for 2-3 hours. Place in the fridge on a wire rack uncovered for 24 hours before either wrapping in clingfilm, ziploc bags or preferably vacuum pack. Leave for at least 2 weeks for the smoke flavour to mature before tasting.
Salmon (cold smoked) - Tesco's skinless, boneless Salmon steaks (about £1.50 each) are great for this. Make up a dry cure mix of 1:1 coarse sea salt and granulated sugar. Spread a thin layer of the cure mix over the bottom of a plastic (or stainless steel) container and lay the fillets, spread out on the top. Cover the top surfaces with more of the cure mix making sure that you get some on the sides of the fillets as well. Cover and leave to cure in the fridge for two and a half hours. Rinse off all the cure mix under a cold tap and then pat dry using kitchen towel. Place on a rack uncovered in the fridge overnight. Smoke for about 8 hours (overnight is great). These freeze well. When required cook at 180 C for 12 minutes.
Garlic - place the whole bulbs in the smoker on a wire rack. They will take about 6-12 hours to smoke depending on how smoky you like them.
While you have the cold smoker on, why not put in a shallow disk of coarse salt. Smoked salt goes well on many savoury dishes.