Can anyone recommend a decent track frame and fork that allows for larger sized tires, up to about 42c? I am looking at the steamroller but anything else you can tell me about is much appreciated. thanks.
Ugly, low quality aluminum, cheaply made to cash in on fixed gears, goofy geometry, terrible for its intended purpose, crappy company over all
42s are bit much to find clearance for on anything that is even remotely trackish. 38 is even pushing it, and its the width I would recomend you hunt for. At 38 I think your best option would be the All City Nature Boy, its basically the exact opposite of all those things, and named after the SIXTEEN TIME, SIXTEEN TIME, SIXTEEN TIME WORLD CHAMPION.
Out of curiosity what rims are you planning on running with you super wides and why?
Why do you want a track bike for your all weather bike? Do you really need to go as wide as 42? Plenty of frames will accommodate 28s, and many will handle 32s. In addition to those listed in the above thread, check out the Wabi classic, which can handle 32s.
Kilo WT will fit up to 45s. Iro Phoenix up to 38s.