Here's the thing Colossus, people are being very careful with you because your posting history gives the impression that you don't seem like you are really putting in the effort to fix what might be wrong with your query and you want an easy solution to your agent dilemma. It seems like you have a bit of an attitude towards agents and queries, and that's a dangerous attitude to have. Because it isn't just about queries. It's about respecting agents.
That's why most people are saying that really, you just need to have a good query. Conference or not. And they are right. It is very likely, even if you do go to conference, you will still need a good solid query letter.
That being said. I do know of authors who got agents at conferences. And they didn't need a query letter. For example, Backspace has an author/agent conference where authors sit at table with an agent, the agent starts to read their work, and then they get it critiqued. I sent a friend of mine their way, and his work was so popular he had two agents offer.
Here is a link to their website:
http://www.backspacewritersconference.com/
But here's the most important thing, the fear of most people posting in this thread is your ego. You might not actually have one, but you are coming across as having one. We are truly worried you are going to shoot yourself in the foot thinking you are an exception and more special than other authors out there, and that you ought to be given special treatment and be able to skip the annoying steps all other new authors have to take.
This attitude (if it does exist) will come across bold as brass in person, trust me. I have seen it. And it ain't pretty. In the end, agents want to work with someone they like and respect. And they can find such people who ALSO have fantastic books.
Now I realise all the above might come across as harsh, likely because I am being very blunt, and you might not be at all any of the above things. But your posting history has already given the impression of someone not interested in playing by the rules. So if my impression of you is wrong (about which I apologise) you should know that at least one person here is getting a slightly not so hot impression of you as an author.
And if one person is, possibly others are. And if you are planning on going to a conference to circumvent the query route, you need to be as delightful and seeming easy to work with as possible and not give off this impression at all.
Again, uber apologies if I am totally misinterpreting you, but I feel like being honest now about my observations might actually be helpful for you later in achieving your goal of representation. Truly.
But if not, you are free to get seriously annoyed by this post and ignore it
. I am truly only writing any of this to help. If it isn't helpful, please, don't pay any attention to it.