How to put my own data on a county map?

[AprilWinchester]

I'm new to this forum and to Arc GIS.  I have a free trial version of ArcMap10 and ArcCatolog10.  I'm trying to creat a county map with my own data.  For example, in Pennsylvania, I have something like this in Excel

County Name     Numbers to Map
Philadelphia       10
Montgomery      20
Chester              5

So on and so forth. 

I tried to add my data to the county map template that comes with ArcMap but I couldn't edit the map.  Then I downloaded a shapefile here http://www.esri.com/data/download/census2000-tigerline/index.html.  But there is no map. 

This is driving me crazy.  I'm sure I'm missing something.  Just don't know what I'm missing.  Could someone help me please?  Thank you so much!

[AprilWinchester]

OK.  I figured it out.  When I was stuck, I was trying to put my data on an Esri base map.  A base map is like an image, which can't have data added.  So, what I did instead was a download a shapefile (and all other supporting files that come with it) of NC counties.  Then I added that map by "Add Data" and then added my own data to that map.  I hope this helped someone.