Need Help Choosing NetWork Modem

I have been given the duty of setting up our new network. We are a nonProfit community center working on a small budjet. We are located in a rural portion of Washington State. We have no DSL or T1 lines at this time. Supposedly sometime this year they should become available. We will have approximately 30 computers networked together. All need to have access to the internet. What are my options? What software is still availble? Our goal is to upgrade as soon as better communication lines become available. I only have so much money in the budjet to spend. Also as you can tell I am still new to this portion of the procedures. I am on a sharp leaning curve so any and all help is greatly appreaciated.