both are correct but "She helped me to find a job in London." is better

Both are correct. 'Help' is unusual in that it can be used both as a causative verb and a non-causative verb. Causative verbs, such as 'let' and 'make', are followed by the object and then a bare infinitive ( 'make me laugh', 'let me come' etc) . 'Help' can be used in this way, but it can also be followed by 'to' and the infinitive. The choice is yours.

both are ok

thanks for your comments!

I agree with what the others have said, personally '''to find a job'' sounds better to me but both are OK.