A couple of days ago I installed bitcoin-qc and loaded the latest block from eu1.bitcoincharts.com/blockchain/. Then to test it out I withdrew a small amount of BTCs from my mtgo account to the address that appeared in the client upon install. Not having received anything yet, I today went to blockexplorer.com and search for that address. The record shows "First seen?: Block 164269 (2012-01-28 19:37:08)" and "Received transactions: 1", but also says "Public key?: Unknown (not seen yet)". The client says today, "Catching up... Downloaded 164146 blocks of transaction history. Last received block was generated 2 days ago". Do I have to send a public key separately? If so, how do I do it? Thanks for taking the time for a beginner.
Your client won't show the transaction until it's received the block the transaction was included in. This website has the block count in the header: http://bitcoincharts.com/charts/
Right this moment, there are 164472 blocks (and I'm responding to your question quickly) so there's clearly still some downloading to do. Try to determine whether the block download is still occurring, and work from there. There should be a percentage complete figure for the block download in the bitcoin-qc client.
You have to wait until the client catches up to the current block (or at least to the block when you sent your transaction). Then the transaction will appear in your wallet.
As for the public key, in most cases it will not be known to anyone until you actually spend some Bitcoins. Details as to why are a bit complicates (you can find them here), but the general idea is quite simple.
When you generate your Bitcoin address, first you generate a private key. From that, you can calculate the public key, but the calculations are designed, so they would be one-way (you can't calculate the private key from the public key). Then, the public key is transformed using SHA-256 and some manipulations into the canonical "Bitcoin Address", and those operations too are one-way. But in order to spend coins, you have to sign a transaction with your private key, and show everyone your public key so they can decode it (this is when your public key becomes known). At that moment anyone can verify what address that public key belongs to (to know if it has any coins), and that you issued the Bitcoin transaction.
In short, wait until your client fully synchronises and you will see your transaction. No action is required on your part in order to receive Bitcoins once the transaction is sent.
[The site doesn't seem to be accepting my comments tonight, so I'll try this.] I found that loading the last block build was masking the real problem. Starting from a fresh install, with appdata empty, I got the progress bar back. But I see that the client was not just slow, it was making no connections at all. Fixed that by setting the port properly in my router/modem firewall as well as the machine firewall. Now bitcoin-qt tells me that it's up to date. Pasting the previous wallet.dat over the new one shows my received coins address as expected. Yet I still don't see the received coins, even though blockexplorer.com shows them to be in the blockchain. Sorry to be still so dim, but what to do next? As I say, the client has been up to date for a day now, through several restarts of bitcoin-qt.