Eric,

Printing barcodes can be as simple as using a Code 3 of 9 Font, which has virually no formatting and is widely used for basic barcoding needs, or as complex as any of the widely used barcodes which require formula conversions and can only be printed by creating a graphic image which must be handled much differently than just using a Font.

Basic Symbologies:
0=Code 39
1=Code 39 ASCII
2=Interleaved 2 of 5
3=Code 11
4=Codabar
5=MSI
6=UPC-A
7=Industrial 2 of 5
8=Matrix 2 of 5
9=Code 93
10=EAN-13
11=EAN-8
12=UPC-E
13=Code 128
14=Planet
15=Postnet
16=UCC-128
17=RSS
Code39

These are all 'widely' used barcodes, each with very specific characteristics and very specific requirements.
If you need to print for simple inhouse purposes, keep it simple and use the Code 39 True Type Font barcode. But if you're going to be dealing with other vendors or manufacturers, like WalMart for example, you will need to get into some rather involved processes for doing even 'simple' projects.

One good source, as Sergey already recommended, is IDAutomation:
http://www.idautomation.com/sitemap/

Regards,

David