The simple answer is to find an actual Trade School for the trade you're interested in. And a good way to do that is to find businesses or unions that are related to that area. Don't be shy -- just find one and walk in and ask. Most people who are involved in a trade for any appreciable length of time will be eager to share their experiences, insights, or at least point you to a training opportunity.
In the area I live in, there are trade schools for construction, welding, plumbing, truck driving, cosmetology, bartending and a whole slew of other professions.
When you want to know how to approach a job, find the people who are already doing that. It's by far the most reliable source of information. And it will also stand a good chance of showing you other opportunities to hone in on your ideal career. And you might just end up like me, spending many years doing something and then many years teaching others to do it.
it really depends on your trade and what you want to do. If it is an actual trade role it may be better to pursue an apprenticeship now and then a college education as something to back you up if you decide to leave the trade. Otherwise in the job economy today it is extremely valuable to have a college degree.
Let me know what trade(s) you're thinking about so myself or others can provide better insight/responses!