How can I find the rate- the fee for- shorting a stock? Let's say I'm shorting 100 shares of google.?

Can I find it on Yahoo finance or would I have to refer to my brokerage firm.

I'm planning on getting two margin accounts- one which I buy and hold a stock and think it will rise in a month, the other account to short any downward trends of that same stock. I thinking about doing this to agriculture stocks like AG and MOS. And yes, I know I hafta do more research.

I am pretty sure there is no fee, I have TD Ameritrade.
They have flat fee for all kinds of trades.
Call your broker or check the fee schedule.
I remember shorting does not cost extra.
BTW are you shorting google tomorrow before earnings?

The only fee is the normal trade fee your broker charges for buying or selling stock. However, it has to be in a margin account and if the trade goes against you (ie, price goes up instead of down) you have to pay whatever, the stock price is when you buy to close your short.

Shorting is selling borrowed stock you do not own (you get money then) with the hope that its price will go down and you can buy to close cheaper. You profit is the difference between sell price and buy price. But if the price doubled, you would have to pay back twice what you got for selling the stock. So you can lose big time if you short right before a rally.

First to short goog it will take a minimum of 22500 in one account and the long position will take the same.

I gave up why would you buy a long position at a higher price if you are going to short it? Why not wait on the lower price.

I fully understand a quick short on a good stock, but not buying them and then placing a short order.

It sounds like you need to learn about the option market.

there are no "fees" for shorting stocks, there are only requirements.

You will not be permitted to have 2 margin accounts
especially for what you want to do.
The two accounts as you described would be considered circumventing regulation T of the Federal Reserve Board which govern the rules for margin accounts

You better go back and learn about trading and more importantly the rules that govern trading,

10% Annually (Give or take a few cents)

You really need to check with your broker.