Below are lists of boats currently for sale on Craigslist.  In addition USODA has a classifieds section where you can find used Optis and gear

Optimist

• E-BOOKS -- 20 E-Books in E-Pub format -- choose from over 400 titles! (N. Kingstown, RI) $25
• OPTI Sail Boat (Jamestown, RI) $1495
• North Sails radial cut Optimist racing sail (Middletown, RI) $500

420′s

• Sails (Northern RI) $50
• Club 420 Sailboat (Cranston) $700
• Club 420- Naval War College (north kingstown, RI) $3500

Lasers

• 2009 Laser Radial Sailboat - (Newport) $4975
• Laser 4.7 lower mast & sail (Jamestown RI) $200
• Laser hull & partial rig (Jamestown) $600
• Laser (Newport) $4950
• Laser with trailer and rigging (bristol ri) $3800
• Laser (Newport Rhode Island) $4500
• Laser Radial XD Sailboat (Newport) $4975
• Laser sail- Full Rig (Middletown, RI) $250
• Laser Daggerboard (Newport) $50
• Laser Sail (Portsmouth, RI) $450