1. He’s here (or in Norway) because of what an armoured heroine might need.
TOM: He’s three quarters of a particle.
3. Confused lad with a messy barnet, he is – crazy!
B
ILL: Invoice him.
FRO
DO: Even when a bit muddled, he knows where his towel is.
6. Formerly supple, before he knotted up.
7. Woven or spun, he stands constant.
Three correct answers.
Ingenious to get Frodo from Ford, (well, I suppose a Dunadan, three hobbits and lots of elves once managed it), but in fact it's an anagram of
frood, so there is no missing letter. And a very close anagram; hence only
a bit muddled.
Ford Prefect himself is a particularly
hoopy frood, of course.