The basic technique is trivially easy - pour vodka (or other spirit) over fruit in a covered jar, and leave for a week or so.
Filter into bottles.
1 liter of vodka over:
a hand of ginger (weight?)
a small pineapple (peeled and chopped)
24oz raspberries (frozen works well)
2 bananas
If necessary, add agave syrup to sweeten.
Other ideas:
http://www.guntheranderson.com/liqueurs.htm
Aniseed - Fennel seed? Star anise? http://www.foodsubs.com/LiqueurAnise.html
Try 1 vanilla bean (split) and 1.5 tsp of anise seed in a quart of vodka; I keep it at full strength but sugar syrup can be added. The naturally sweet flavors seem to make this redundant, though. enjoy!
Almond - normally made from apricot kernels?
http://allrecipes.com/Recipe/Amaretto-2/Detail.aspx