The most recent Haskell Family Association Reunion was held April 21/22, 2006, Charleston, South Carolina.
Mt. Pleasant Holiday Inn, 250 Johnnie Dodds Blvd., Mt. Pleasant, South Carolina, 29464.
Several sets of pictures from the reunion are available at Webshots.com: a set from Tom Haskell, pictures from Jim and Melissa Haskell, and some photos provided by Helen Haskell and Bar Blackman
Some background information on Charleston:
Tom also has pictures from the Danvers Haskell Family Association reunion, which took July 27 and 28, 2002 in Danvers, Massachusetts
The 17th Annual Reunion for IHFS will be June 20-23, 2007 with a special invitation to North American visitors. The traditional 16th Annual Reunion meets June 25, 2006 in Cranborne.
Keep track of the details at the International Haskell Family Association website. Correspondence: Pat Haskell, IHFS Secretary
Tom's Webshots page also has pictures from the 14th Annual Reunion of the International Haskell Family Society, which took place June 14th, 2004. Reunion pictures are in the Album "IHFS Reunion and Tours Part III".
Salisbury, England was the headquarters for this reunion.
Ira J. Haskell's Chronicles of the Haskell Family, the Haskell Anthologies, and other documents are generally available from Higginson Books: 
The Haskell Family Association is a nonprofit organization with the following objectives:
An application for membership [PDF format] is available.