WikiRhymer has about 2,000 rhyming words and phrases for "frog" starting with...

Words that have identical vowel-based rhyme sounds in the tonic syllable. Moreover, that tonic syllable must start with a different consonantal sound.
bog
    clog
      flog
        fog
          hog
            jog
              slog
                smog
                  nog
                    agog
                      pirog
                        prolog
                          Fogg
                            Haag
                              Hogg
                                Maag
                                  Ogg
                                    Prague
                                      Waag
                                        • eat high on the hog
                                        • go the whole hog
                                        • go whole hog
                                        • high off the hog
                                        • off the hog
                                        • on the hog
                                        • road hog
                                        • whole hog
                                        Pure Rhyme Set #1 of 1 (Add to/Edit Set Members)
                                        Words that have a pure rhyme on their last syllable only.
                                        prologue
                                          gulag
                                            backlog
                                              eggnog
                                                groundhog
                                                  hedgehog
                                                    waterlog
                                                      demagogue
                                                        Herzog
                                                          Hertzog
                                                            Tagalog
                                                              End Rhyme Set #1 of 1 * (Add to/Edit Set Members)
                                                              Words that "almost" rhyme on the vowel-based rhyme sound of the stressed syllable like: be/eat or maybe/shapely. (Click for more info)
                                                              Bronx
                                                                Tonks
                                                                  Near Rhyme Set #1 of 101 (Add to/Edit Set Members)
                                                                  twang
                                                                    Hwang
                                                                      Kang
                                                                        Kwang
                                                                          Tang
                                                                            Zhang
                                                                              Near Rhyme Set #2 of 101 (Add to/Edit Set Members)
                                                                              bonk
                                                                                bronc
                                                                                  bronk
                                                                                    conch
                                                                                      conk
                                                                                        honk
                                                                                          wank
                                                                                            Cronk
                                                                                              Near Rhyme Set #3 of 101 (Add to/Edit Set Members)

                                                                                              Get Pro Features!

                                                                                              To see all the near rhymes sets, you must "Go Pro." It's only $7.00 a year!

                                                                                              I want to "Go Pro"

                                                                                              Rhymes made up of more than one word. For instance, "jealous" and "tell us" or "shaky" and "make me."

                                                                                              No mosaic rhymes for one-syllable words.