The easiest way would be to "nest" the tables in another table. The parent table will have only two cells:

<table>
<tr>
<td style="width: 50%;">

<table>
<tr>
<td>&nbsp;</td>
</tr>
</table>

</td>
<td>

<table>
<tr>
<td>&nbsp;</td>
</tr>
</table>

</td?
</tr>
</table>

Alternatively you could set the align attribute on the first table, to say align="left" - the 2nd table will follow along side the first one (to the right).

<table align="left">