<form name="my_form" method="get">
First Name: <input id="field" name="first_name" type="text">
<input id="submit" type="submit" value="Add" name="submit" />
</form>
style.css
#submit
{
width:70px;
height: 31px;
border: 1px solid #000000;
vertical-align: bottom; /* or vertical-align: top; - will set text and submit to same line */
}