How do I find a website that lets you look up serial numbers?

Serial number are no use at all. It is just a record for that individual watch. It was the 385th watch made in March 1990.

Look on eBay for prices realized on sold items.

https://www.google.com/search?q=pulsar+quartz+watch+value

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if you can't see it on the back, it's probably inside the back cover.

SORRY BUT - You are on the wrong website for this type of inquiry. This is a community based self-help website for the repair and use of manufactured products made for consumer use..

Check out the brand/manufacturer name and the serial number. Google out the contact number for the customer service for that brand/manufacturer and once you speak to them, provide them the serial number, they will answer your query to your expectation.
Regards,
Harry
[email protected]
+1 (503) 583-2414

It's much easier to date vintage Bulova watches by their "year code" than by their serial number. If you look carefully, usually above or below the serial number, you'll see a little alphanumeric code, like L5, N3, or P6. These can be translated as follows:

Lx = 195x Mx = 196x Nx = 197x Px = 198x Tx = 199x

Older Bulova watches used little symbols to show the year of manufacture. A picture of those codes can be found here, as well as elsewhere on the Internet: http://www.manleyhorlogerie.com/Watch_History/bulova.htm#Bulova%20Date%20Codes

serial number odf idm is a great problem

Serial numbers are generally on the back of the watch.

You may be able to find two or three numbers on the watch.

A case number, a movement number and a serial number.Alternatively you might find a style number (which in your case is 26B44) and a serial number.

Yes they do;

To see this go to the TAG web site "tagheuer.com" and select "watches".
Now select "aquaracer" and you will see a list of variations.

1965 theres a full breitling serial number list at http://www.brittons-watches.co.uk/watches_breitling_dates.htm