Need wireless access between main house and 2nd building on the property

That is a long distance for wireless to go. I have a top notch Wireless G Router and it will not go 400 feet (I have tried it).

I suggest you put an ethernet cable from the house to the cottage. True you have to bury it, but (a) it will work and (b) there is no monthly expense.

You can still hook up a wireless router in the cottage off that ethernet extension.
... Thinkpads_User

see this - http://www.wirelessforums.org/alt-internet-wireless/connecting-two-buildings-about-400ft-away-1699.html

I have seen wireless go about 400 feet at a golf club before.

I can make the distance, but signal strength was (a) very variable and (b) generally low.

... Thinkpads_User

Eirman:
rfc1180:

I will check out the sites you provided. I was sure there are some Amplified solutions out there that will work with your conventional over the counter wireless routers. I assume that I should Wirless G instead of Wireless N technology with these mentioned devices. What do you think?

I agree with the directional antenna choice, but go with N.

N isn't much more expensive, and is designed to go greater distances.

I doubt they are on the same electrical box... but if they are, look into using a powerline adapter!
I picked up a few of them for $20 each... saves my WiFi for our iDevices.  Other things (stationary laptop, home theatre PC, etc.) all use our home's electrical wiring to access the internet.

All great ideas,
nap0leon: I just confirmed that the cottage is a little under 250 away. Yes, they are on the same Electircal panel as the main house. I may give the "powerline devices" a try. I have a pair from Netgear. I havn't had great luck and/or performance with them but this is a different enviroment

ks_admin: I guess N would work. I believe its still part of the 802.11.

Eirman: These options seem to be the best and I'm seeing good feedback from them
rfc1180: this might be more then I really need. I think your url points to a product that will be well suited for two business buildings who can take advantage of 100mb speeds

Do you think the fact the two buildings are under 250ft - having a wireless N for adapter and router may work in a straight line - or perhaps still alittle too far. If not, going with the antenna's would be the best choice.  And if I do go with the antenna, keeping everything "wireless N" is most likly still a good choice. I still hear that Wireless G options are more stable.

I am considering the cable run as well. But that is quite a bit of work But at the same time, the very best solution.

Great Solutions!