First time trying a code golf solution, managed to do Part 2 in 231 characters.

  p="one two three four five six seven eight nine".split();sum(int(x[0]+x[-1])for x in["".join([["",s[0]][s[0].isdigit()],str(p.index(w)+1)][s.startswith(w)]for s in[l[i:]for i in range(len(l))]for w in p)for l in open("input.txt")])