Homeopathic remedies are chosen based on comparing the specific symptoms that you have with the specific symptoms associated with a remedy--since one person's sore throat symtpoms may be completely different from another's, the remedy may be completely different, as well. The secret is to find the remedy that fits your symptoms, rather than using the remedy that worked for Mary.

A Rhus Toxidendron sore throat would feel dry, with a tickling in the larynx, it might have been caused by straining the voice, but it would improve from use.

A burning sore throat, with ulcers would respond better to Arsenicum.

If you are going to use homeopathic remedies, you need to get a a Materia Medica, which includes the symptoms associated with each of the remedies (there are several thousand) and a Reperatory, which is an index of the symptoms and the remedies that go with them.

There is a very good book called "The Complete Homeopathy Handbook" by Miranda Castro, St. Martin's Press, with an easy to understand Materia Medica and Repertory, that you can find at Borders, or perhaps at your natural food store for around fifteen dollars-- it also explains how to collect the symptoms and figure out the remedy that is best--