There are two different types of book. One is the Seamans Card (and is Red) the other is the Seamans Discharge book (which is blue), its the blue one you need.
Normally all you need to apply is a letter from your company stating that you work onboard a particular named vessel for them, the vessel MUST be UK registered as far as I know – that may be a problem nowadays!
You will have to pay for the Discharge book yiourself unless it is a requirement by your employer that you need one.
You normally get the book signed and stamped by the vessel when you leave .
The general rules are that you must spend 183 days in any 365 day period out of the UK. You must also have one foreign port call a year as well. When you come back into the UK, half the total number of days must always be more than the number of days you have spent in the UK.
e.g. at the start of your claim period, you leave the Uk for 30 days, you come back into the UK for 30 days, you leave for 30. When you come in next time, total days =90, half=45, total in the Uk to date is 30 therefore you pass. Basically you need to know how long you will be out of the UK next time to know how long you can stay in this time.
Google "IR205(S)" and download the information from the Tax Office which includes a form where you just fill the dates in and it does the calculations for you. There are other little rules and quirks, best you find out all about them.
Read http://rovworld.com/phpnuke/modules.php?name=Forums&file=viewtopic&p=4044&highlight=#4044 for a lot more info.
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