I've read everything I have on Vermouth and must admit that I think it is far too complicated and exacting for me, and I'm really not prepared to write a multi-page recipe involving microgram measurements of 18 different herbs--several of which I've never heard of--when I haven't tried it myself. If you want to pursue making your own Vermouth, all I can do for the time being is refer you to "The Chemistry and Technology of Wine and Liqueurs" by K.H. Herstein and M.B. Jacobs, published by Chapman and Hall, Ltd. If I obtain a simplified recipe, I'll post it here for your reference.
Port wine, however, is a different matter. Two words of caution. First, port wine yeast is essential; use no substitute. Second, port is a fortified wine and this recipe uses brandy as a fortifying agent; do not use flavored brandy. Finally, this recipe makes six gallons of Port. I do not see any way to reduce the quantity except to halve or third the recipe and make either three or two gallons. Since the grape concentrate he refers to comes in both gallon and half-gallon cans, halving the ingredients may be the better option if you don't want to make six gallons.
Prepare yeast starter 3 days in advance according to instructions on yeast packet. Separate banana chips in primary, add elderberries, grape concentrate, water, 1/2 sugar (6 lbs), yeast energizer, acid blend, and crushed Campden tablets. Stir well to dissolve sugar, cover well, and wait 24 hours. Add yeast starter and stir gently once a day. When specific gravity is 1.040, draw off 4-6 cups of must, slowly dissolve additional 3 lbs of sugar into it, then stir it into primary. When S.G. is at 1.030, strain out elderberries and banana chips and siphon wine into secondary. Attach air lock and check S.G. daily. When S.G. is at 1.010, draw off another 4-6 cups of must and slowly dissolve remaining 3 lbs of sugar into it. Gently add this back into secondary. Rack as deposits form, but not more often that every three weeks. When no more deposits form, allow one month for wine to clear. If wine fails to clear, stabilize wine and add fining according to instructions for particular fining agent. Wait 10 days, rack wine one last time, sweeten to taste, then add 60 oz brandy and bottle wine. Age one year before tasting or using for cooking. [Adapted from Stanley F. Anderson and Raymond Hull's The Art of Making Wine.]
My thanks to Gary Thompson for the request.