Here is the best conjugator I have found. You can enter any form of the verb: http://cooljugator.com/ru/?query=%D0%BF%D1%80%D0%BE%D1%81%D0%B8%D1%82%D1%8C&stress=1
I also really like openrussian.org - it has the info presented in a slightly different way than the site given by Dejo, but has also has a bunch of example sentences that are particularly useful... http://en.openrussian.org/ru/%D0%BF%D1%80%D0%BE%D1%81%D0%B8%D1%82%D1%8C
«Я расту» means «I am growing». «Я ращу» means «I grow something». However, the word «ращу» (in the infinitive — «растить») is used very rarely and mainly in expressions like «Они растят детей» (They are raising children), when other words of the same root are less appropriate.