My house has a steady but slow leak coming from one of our pipes in our crawl space below our house. The area in which the pipe that is leaking is very small are hard to get into... is there anything special we could use to stop the leak until we can get a plumber here during the week?

Kind of depends on where the leak is and what king of piping.

Is it Sewer leak or Water pipe leak ? If Sewer leak than it is a health hazard. After couple of weeks, you will get this awful smell with tons of sewer flies that will enter your living space through floors. Also, odor will be escaping through crawl space vents and will be noticeable around the exterior or the house. If it is Water leak than you should deal with it ASAP as water my cause house foundation to sink. Either way, I suggest you deal with it in timely manner

Milo

In the mean time turn off your main except when you must have water.