Rhode Island does not currently have a State Wide Referral Program.
Here are some links to spay/neuter programs in your state. Please contact them for more information on finding affordable spay/neuter in your state.
Rhode Island Spay/Neuter Clinic
http://www.ricsnc.org/
Warwick, RI
Rhode Island VMA Assistance Program
http://www.rivma.org/owners/spay-neuter-assistance-program
All Rhode Island
Providence Animal Rescue
http://www.parl.org/programs/pet-owners
Salmon River Vet Services
http://www.rimobilevet.com/
Riverside, RI
Pet Partners
http://www.petpartnersne.org/spayandneuterinfo.html
Fall Rivers, MA
Medfield Animal Shelter
http://www.medfieldshelter.com/spay-neuter
Medfield, MA
Luke & Lily Lerner Spay/Neuter Clinic
http://vet.tufts.edu/lerner-spay-neuter-clinic/
North Grafton, MA
Stop Spay/Neuter Clinic- Mobile Clinics
http://thestopclinic.com/
Lots of Locations