if you want change the color of ActionBar just do this:
ActionBar bar = getActionBar();
bar.setBackgroundDrawable(new ColorDrawable("COLOR"));
see the following link for more info
and if you using ActionMode This is the style used for any ActionMode. You'll need to create your own style to customize it
<style name="Widget.ActionMode">
<item name="android:background">?android:attr/actionModeBackground</item>
<item name="android:backgroundSplit">?android:attr/actionModeSplitBackground</item>
<item name="android:height">?android:attr/actionBarSize</item>
<item name="android:titleTextStyle">@android:style/TextAppearance.Widget.ActionMode.Title</item>
<item name="android:subtitleTextStyle">@android:style/TextAppearance.Widget.ActionMode.Subtitle</item>
</style>
more info in this site
see this too
Edit
for pre-Honeycomb see this please