A client of mine told me that he is planning to attend a big trade show in a major city in a few weeks and that he is planning to take his resume and pass it around to his contacts there. I can't help but feel that approaching a job search in that manner seems a little bit desperate. This particular client is not, in fact, desperate for a job but handing out a resume in a non-hiring environment like a trade show doesn't seem "right" to me.
I don't know if there is a right or wrong answer to the question but my advice to job seekers would be to use the trade show to make contacts but wait until after the show to follow up and send resumes. Most vendors at trade shows are very busy promoting their products or services and even if you know them well your resume probably won't get the attention you want it to at the show. And its possible the document could be lost or misplaced on the way back to the office.
Use trade shows and events as great opportunities to meet new contacts and to express an interest in their companies, products or services. Exchange business cards with your new contacts and wait until a few days after the show to follow up. Give your new contacts a chance to get settled back in the office before you approach them about what you want: a job. In fact, I would probably recommend that you exchange a couple of emails before you send your resume along unless your conversation at the trade show specifically addressed job openings at your new contact's employer. You can sell yourself without being inappropriately pushy and handing out a resume too quickly can seem pushy, desperate, or just obnoxious.
The exception to this is, obviously, if you meet a contact at a trade show and if he/she says, "Hey you are in luck, my company is looking for someone just like you right now. Do you have a resume I can show my boss? If he likes what he sees maybe we can meet for breakfast tomorrow." It wouldn't hurt to have a few copies of your resume with you at a trade show (or an electronic version) with you but don't hand it to anyone who hasn't asked for it first.