• Quaternary Environments Network maps of paleo-vegetation.
• Geospatial Analysis Glaciated Environments see Data Archive section and instructions for zip file.
• PALE PALEOCLIMATES FROM ARCTIC LAKES AND ESTUARIES
• Paleoclimatology at NOAA
  • Peltier Topography and ice occurance (data also appears to be here)
  • PaleoGCM output
• Laurentide Ice Sheet retreat animated gif

From Steve F.:

• Paleoenvironmental records of postglacial climate change in the Prairie ecozone
• Estimating Temperature and Precipitation at the Last Glacial Maximum
• USGS - Gridded Sea Level - Pliocene and Late Quaternary
  
  

The Arctic Precipitation Data Archive (WMO)

APARD - Arctic Paleo-River Discharge at AWI - Bremerhaven