DX'peditions/Contests:

• NG3K - Announced DX Operations
• NØHR - Upcoming DXpedition Map
• The Daily DX
• NG3K - Contest Resources
• Contesting.com

DX Spotting Nets:

• DX Summit
• F5LEN Webcluster
• DX Watch

Propagation:

• ARRL Propagation primer
• ARRL Propagation Bulletins
• ARRL Keplarian Data
• HamRadio On-line, Radio Propagation Conditions
• NW7US - Propagation, Space Weather, & Sunspot Resource Center
• Spaceweather

Software:

• Tucows - Windows software
• Shareware.com
• Amateur Radio - Shareware To Go
• The DX Zone - Software Collections
• 59+ Software - Log, Contesting, DX, more ..
• N3FJP - Amateur Radio Software