I agree with Mike’s post — there are some things the Lord just leaves up to us to solve in our discretion. In other words, the Lord trusts us to make decisions (at least, some decisions – there are some where He deigns to give us His explicit direction). But I have a beef.
The beef is this: just because the Lord trusts us to make our own decisions does not mean that those choices don’t matter or are unimportant to Him. The temptation is to say that if God doesn’t send His angels to tell me whether or not to go to law school, well, that’s because He doesn’t care whether I go or not.  This is not the case. I don’t believe in a God who is uninterested in our affairs. I believe in a God who deeply, deeply cares about our lives — even (or perhaps, especially) in those aspects where we don’t care ourselves.
In fact, the scriptures tell us to cry to the Lord, to importune him regarding these things, even though they seem mundane. We are commanded to pray always, but in case that is ambiguous we also have specific direction, in Alma 34:
17 Therefore may God grant unto you, my brethren, that ye may begin to exercise your faith unto repentance, that ye begin to call upon his holy name, that he would have mercy upon you;
18 Yea, cry unto him for mercy; for he is mighty to save.
19 Yea, humble yourselves, and continue in prayer unto him.
20 Cry unto him when ye are in your fields, yea, over all your flocks.
21 Cry unto him in your houses, yea, over all your household, both morning, mid-day, and evening.
22 Yea, cry unto him against the power of your enemies.
23 Yea, cry unto him against the devil, who is an enemy to all righteousness.
24 Cry unto him over the crops of your fields, that ye may prosper in them.
25 Cry over the flocks of your fields, that they may increase.
26 But this is not all; ye must pour out your souls in your closets, and your secret places, and in your wilderness.
27 Yea, and when you do not cry unto the Lord, let your hearts be full, drawn out in prayer unto him continually for your welfare, and also for the welfare of those who are around you.
And so, yes, God may not tell you whether to get that burrito smothered (yes, get it smothered) or what route to take on the way home (avoid I-15), but that does not mean that (a) we should not ask Him these things or (b) that He does not care. We mattereth to him.
 Don’t go to law school. Seriously.