I wonder how common or available that is for most Catholics.  In addition, for the boys especially, how do these schools compare with those of the secular world when it comes to getting a job to support a future family?  

My daughter's college (and I suspect most traditional/conservative Catholic colleges) is for liberal arts.  That means it is from a tradition of education for its own sake rather than leading towards a job.  It may be useful for those who need a bachelor degree before going on to law studies, seminary, etc., but it is not really job oriented.

If a young man wishes to quickly get a job to support a family, I think he is better off being apprenticed to a trade than going to college, although there may be some exceptions to that.  In general, apprenticeship is better for practical skills.  Also, secular colleges immerse students in attacks on their faith and virtue.

Maybe I am misunderstanding your concerns, 2Vermont.
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But because JAne says that a young man is better placed to get be apprenticed, does not mean he is restricted to that option. There are other options and homeschooling is not an impediment to using them.
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IN the case of my two sons, one went on to study ancient languages and now doing a masters in theology, while the second went into the navy and eventually became an electrician. Our third, a girl, qualified as a registered nurse.
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This is how we did things:
AS each of  our three children reached 15 years of age, we sent them to do a 6 month pre-trade course at TAFE. NO 1 commercial cookery, no2 carpentry and no3 retailing. THe main aim was to do something practical and to get them known to the TAFE institution, and to become familiar with dealing in a classroom situation.
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AFter the 6 month stint each went back to complete his homestudy.
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At 16 each then did a matriculation course at TAFE which each completed in one year with flying colours, and the two who desired to study at University did.
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WHen we went for an interview for the matriculation course, I got my son to assemble a sample of his work. AT the interview we were told we did not need to show it as "We find our best students are the homeschooled."
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Our second son and daughter got in on the strength of our first son's reputation. SO you see there is more than one way to skin a cat!
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Have I gone some way to answering your question?

Unfortunately, that doesn't leave many options for Catholic men who have to make a living in the secular world.

Nonsense, my big Italian family grew up homeschooled and all the men went on to trades and most are all raising families on one income. And these guys are currently in their 20’s and 30’s. We have electricians, mechanics, welders and construction foremans. And only 1 put himself through trade school. A few did get their high school equivalency test, but others did not and just started out as an apprentice. My 18 year old son is working full-time as a car mechanic’s apprentice and he has no diploma. At this time he believes that his vocation is to get married and raise a family so he is already working hard for that purpose. 
Now granted, these jobs are blue collar, get-your-hands-dirty kind of work, but all the same, trades are great professions, and considering Jesus and St Joseph’s trade was Carpentry, it can follow in Saintly Footsteps too.  :)