Hi I haven't been on the forums in forever, but let me give you some advice from a published/produced playwright.
a) A page does not always = 1 minute. That's a general rule in film scripts but the nature of theater is different. A page could be 45 seconds or it could be 1.5 minutes or longer. It all depends on what is going on in that page of script, how much is dialog, how much is action, etc. What I would suggest is contacting a local college, see if they have a theater club, invite them over for food, drinks, etc and actually do a reading of the script with a timer so you can get a feel for how long the script is actually.
b) Start looking for contests to submit to. Many theaters do hold contests or submission opportunities for long plays, short plays, 10 minute plays, one minute plays etc. I am part of a group that calls itself "The Offical Playwrights of Facebook" on Facebook and every month the main moderator makes a list of every contest or opportunity that expires that month. There is a similar group (with a lot of the same members) on Yahoo! called "The Playwright Binge".
c) Join the Dramatists Guild of America. You don't need to be published or produced, as long as you have written a play. It costs approximately $100/year. It's worth it. They will help you with any legal help you may incur (including helping with contracts) and they will fight for your rights as a playwright.
Hope this helps