If you need to, just type in the word and add the word rhyme - that will usually get you a selection.
Don't just go by the straight spelling, however. There are often a number of ways of spelling the same sound.
You can also use half rhymes that use either the vowel sounds or the consonants to rhyme. Also similar sounding consonants can be swopped to find an assonance - so change an N for an M, a P for a B, a V for an F etc - which can leadd you in a different direction for a neat end to a line.
When you are doing that be conscious of two things
1. Know where you would like to go in the story of the song, but don't be afraid to follow a new route if you get a kicking hook arising out of the rhyming process - just drop things and go !
2. Don't just find a rhyme and give up - try and get the rhyme to fit without breaking the song to fit the rhyme.
Last thing - if you can't get a rhyme - revise the whole song, you may be able to find a sweeter way to say what you mean to say.
"Don't play what's there, play what's not there." Miles Davis