Agents have been writing to us about a new type of "scam" they are seeing: agent middleman services. These are companies that, for a fee, will query agents for you. Agents overwhelming ignore queries from these companies. If you are having trouble getting an agent to represent you, your best plan of attack is to work on your manuscript and research the field. Join a critique group, attend an SCBWI event and make sure you are querying the right agents by searching though the agent directory in The Book. Paying a third party to query for you is not a fast track, it is just a waste of your money.
As agent Mandy Hubbard said on Twitter:
Find out about other shady business practices to watch out for at Writer Beware