You are doing the right thing by wanting to learn wedding photography from someone already working at it - too many people are getting in over there heads by trying to photograph weddings without any real experience.
The key requirements from any assistant are, in my opinion, enthusiasm and desire for knowledge.
First, find a photographer in your area whose work you like. You can call them or email them, just to politely find out if they are taking on assistants etc. You might want to ask about being an apprentice with them - they may not pay you at all in money, but the knowledge you will gain will be worth more than any amount of money.
To begin with you will probably just be carrying gear, doing setups and take-downs, helping with groups but not taking photographs. That will come with time.
Anyway, hope this helps and good luck with your search.
Nigel