help with sed or awk with less pipe

Shell Programming and Scripting
1 

<tr><th align=right valign=top>Faulty_Part</th><td align=left valign=top>readhat version 6.0</td></tr> <tr><th align=right valign=top>Submit_Date</th><td align=left valign=top>2011-04-28 02:08:02</td></tr> .......(a long string)

I want to get all the field between "left valign=top>" and " </td></tr>" with awk or sed with less pipe

something like :

readhat version 6.0 2011-04-28 02:08:02 ......

any help?

2 
$ nawk -F"[<>]" '{for(i=1;i<=NF;i++)if($i~/left valign=top/){print $(i+1);next}}' input.txt
readhat version 6.0
3 
$ awk -F\> '/^td.*top>/{print $NF}' RS="<" ORS=" " inputfile
readhat version 6.0 2011-04-28 02:08:02