If I had my time machine I would travel to pre-1928 China, say maybe 1920 or so, becasue I think that year a lot of knowledge was lost in China with some of the political problems and the burning of the Shaolin temple (again). I don't know who I would go to first, or where, but having a time machine I could of course figure that out at my leisure.
I'd have to learn chinese first. But I have a time machine so I can do that in no time.
I'd go back in time until just before kung-fu arrived in Okinawa, and I'd be there waiting for it... "Oh, look, a ship-wrecked sailor, I wonder if he knows any kata?" LOL
I would be waiting outside the cave on day 40 when Boddhidharma finally decided it was time to teach the monks...
I guess I should probably do these things in chronolgical order...
And, or course, I would be waiting on the docks for little Jimmy Mitose to get off the ship from Hawaii, and I would use my time machine to periodically monitor him so that I could find out what the heck he really learned and from who.
I don't know if I would train with Musashi, but I would certainly travel to see his duels. Especially the on with the master of the spear, because I want to see what Musashi meant when he wrote, after the duel, that he "fought him in the style of jujitsu" and that the opponent "could not get with 5 feet" of the unarmed Musashi.