You're right to be suspect of certain practices used by recruiting agencies, but to throw the whole lot out seems a bit extreme. Some of the better agencies (and there are good ones out there) do take the time and energy to work personally with you in identifying those opportunities that represent the best fit for you, and then only approach those targeted employers on your behalf. The service they render is much more thorough than "just blasting your resume to every company in your industry," as you've stated. They have established relationships with employers -- employers who have come to them and contracted for their services, knowing that these recruiting agencies will deliver only qualified candidates. It can save the employer countless hours and the recruiter fee is anticipated and happily paid to secure the right employee. So, let's not discount them all as useless!
The trick, of course, is to find reputable companies that value honesty and integrity and render first-rate service; not only to their clients (the employers) but also to the candidates they try to place. It's true their first loyalty is to the company that pays their fee, but if they do their jobs well, they will offer the same kind of dedication and thoroughness to the candidate pool, so a good match is made for both sides. They also are able to open doors that might otherwise be closed to a job hunter. Many employers will only work with a trusted recruiting agency, so it's important for candidates interested in those companies to also establish a relationship with the recruiting company. Just sending your resume directly to the company might not bring the results you desire.
So, what can you do? The answer, of course, involves some detective work on your part and a willingness to vary your job-hunting approach from company to company. Find out if the companies that interest you work with recruiting agencies, and if so, which ones. You might try calling the company directly and just asking them if they use a recruiting agency and see if they will give you the name of that agency (or agencies). Or conversely, call recruiting agencies that have been recommended by either someone you trust or a former client and ask for the names of some of the companies they service. They may not be willing to tell you, but if you don't try, for sure you won't get any information.
Smaller companies may be more willing to talk with you than larger ones, who now rely heavily on e-mailed resumes from candidates and don't respond much, if any, to direct approaches. For more information on this, read Perri Capell's article E-Mailing Resumes to Recruiters Won't Generate a Big Response.
For any agency that you contact, make sure it has been around for a while and has established some kind of verifiable track record. If a company won't give you any kind of information you can verify about how it does business and what results it has achieved, keep looking -- it may be the very kind that sends out your resume without providing the kind of service you really need.