http://www.airspacecoordination.org/
A list of sites are at the bottom of the page.
It's common for TFR's to crop up while you're enroute, however; these don't exist at the time you depart. You're still responsible for avoiding the TFR.
One thing you can do is request VFR radar advisories ("flight following") when going cross country. It's no guarantee either, but it's a help. Depending on the length of your cross country, you can also contact flight service enroute and request updates of weather and flight restrictions/NOTAMs.
If you happen to see smoke, avoid it. Report it from a distance, but keep your eyes open for other aircraft which may be working the fire or enroute to or from the fire (bear in mind that those aircraft may be working five or more radios simultaneously, and some may be dealing with reduced visibility due to ash, retardant, and other fire products on the windscreen). Avoid those areas; they can be very congested and while everyone should be looking out for traffic, what they don't need is you in the airspace making one more hazard. It's hazardous enough.
You can't have real-time constant downloading or checking of NOTAMS or TFR's as you fly from A to B, but you can be thorough before departing, get updates as you go, and get with ATC where you're able to at least try to stay current on TFR's and other issues as they arise.