Bill,
No problem, I can give you atleast a dozen or more from my various tanks. I do not mind passing these guys on, I got them free from various petsmarts. All you need to do is ask for them and they are nice enough to give them to you.
I have never complained about having snails, I know the best way to control them is to control the amount of food going into the tank, less food, less snails. But I do enjoy having a variety of inverts in my freshwater tank, snails and shrimps.
As for brackish settings, I tend to have my tanks around 1.005 or lower. I know they can be higher around 1.010 - 1.020.
A great website for Brackish tanks is
Badman's tropicalfish .
As for other inverts, i hear you can acclimate shrimp for a brackish tank.
jim