@Peachey: Base word in that example is "sklad".
There is difference between skladník (warehouseman) and skladateľ (composer). :)
Anyway, I think that nouns are made from verbs. We have it in Slovak too. I think it is more tricky:
čítať (to read) - čitateľ (reader - person), čítačka (reader - appliance), čítanka (book for kids to learn read)