Diane I am taking courses in GIS so am not an expert but there is a script available that is called "Nearest" and this works on point line poly queries and will assist in proximity work.
This can be found under the help menu look at sample scripts and then just click on the nearest script or the one that describes this analysis of proximity and load it into a new script by either copy and paste or reference a file you may store it in.....and then compile it (hit the check button) and then click on the layer view or scene that you are working in and then back to the script and hit the run button (looks like a person running) and this will create a table of reference values...You'll be prompted first for a "source theme", and then a "search theme". You must decide what is what by your search needs (say nearest camp ground from park theme)
When prompted for a "search field", choose a field in your table (camp sites ID)
Last, when prompted for a "search value", choose type of camp site or type of item in the list in your tables search field.
Considering the amount of time ago that you asked this question you may have already discovered this but in any case hope this is food for thought.