Refoaming instructions:
http://www.partsexpress.com/Tech/260-915.html
Speaker replacement basics:
http://www.partsexpress.com/resources/spkbasics.html
Foam surround kits:
http://www.partsexpress.com/webpage.cfm?webpage_id=3&SO=2&&DID=7&CATID=49&ObjectGroup_ID=373
Check the crossovers for burnt resistors and replace them with exact replacements, same resistance, wattage, type, tolerance, etc.
Also you may want to replace any electrolytic capacitors in the crossover networks with EXACT replacements. Same value, voltage, non-polarized, etc:
http://www.partsexpress.com/webpage.cfm?&DID=7&WebPage_ID=61
Especially the smaller ones as low value lytics are notorious for drying out, changing value, and becoming leaky over time.
