Question
I live in Florida & planted a Meyer Lemon tree almost 2 years ago.
There were 3 lemons on it when I bought it , since then I have only had 1 lemon. Just a few weeks ago it was full of blooms but all the little fruit buds have fallen off. I fertilize every 6 weeks with a citrus fertilizer. It gets several hours of sunlight daily. I have no idea what to do to get it producing fruit. I only water if we have not had any rain.

Answer
It sounds like your lemon tree is receiving lots of love and care which is wonderful.  The problem sounds like the flowers are not getting pollinated.  If you only have one lemon tree, you really need at least one more.  Lemon trees are more likely to produce fruits if they are pollinated by another tree (cross pollinated) then if they must self pollinate.  

Once you have a second tree, monitor for insect activity.  Most lemon flowers are fertilized by insects.  If you do not observe bee activity at your flowers, you may have to help things along.  There is an eHow article that explains how to do this:
http://www.ehow.com/how_8041074_pollinate-lemon-trees.html