nutrient additions

can someone give me the skinny on this? what to use, when to use it, and where i can most likely find it?

Yeast nutrient is there to help the yeast survive and multiply and stand up the the high alcohol.
I got my yeast nutrient at the home brew store. it was 1 tsp per gal when you pitch the yeast.

If you dont have a home brew store near ya...Go online and search for best price...

so, this is my understanding of the nutrient..If i am wrong someone wiser than me will chime in

The problem is, is most wine yeast were developed for grapes which are rich in the req'd nutrients. Most other fruits and honey lack those nutrients, so we must add them to help those lil buggers to eat sugar, fart co2 and piss alcohol.
DAP (DiAmmonium Phosphate)is the most commonly found in brew stores IMO, fermaid k is a complete nutrient that contains DAP, amino acids and other goodies for the yeast and can be a little difficult to locate in stores but easily found online. Some mazers use raisins as a alternative/natural nutrient source.
If you go the raisin route add them to the must in the beginning and rack off when you transfer to the secondary. DAP and Fermaid K can be dumped in all at the beginning but many prefer the staggered nutrient method. Just follow the directions on the bottle or bag of nutrient as for the dosage.