To add the Facebook Like Button and Google's new +1 (Plus One) button to your Ning Network, add the following code to your Custom Code Box, via My Network/Tools/Custom Code;

Google +1 Button Only
<!-- G +1 All Pages Above Sign-In -->
<script type="text/javascript" src="http://apis.google.com/js/plusone.js"></script>
<script type="text/javascript" language="javascript">
x$("#xg_module_account").before("<div align=center id='custom_g1'></div>");
var g1_html = '<g:plusone></g:plusone>';
x$("#custom_g1").html(g1_html);
</script>

Both Buttons (Facebook Like and Google +1) - - this is my code. Be sure to change your facebook settings as you want them. If that makes no sense, not to worry. Just use this code:

<!-- Facebook All Pages Above Sign-In -->
<script type="text/javascript" language="javascript">
x$("#xg_module_account").before("<div align=center id='custom_fb'></div>");
var fb_html = '<iframe src="http://www.facebook.com/plugins/like.php?href='+window.location+'&layout=standard&show_faces=false&width=180&action=like&colorscheme=light" scrolling="no" frameborder="0" allowTransparency="true" style="padding-top:15px; border:none; overflow:hidden; width:180px; height:50px"><\/iframe>';
x$("#custom_fb").html(fb_html);
</script>
<!-- End FB All Pages Above Sign-In -->
<!-- G +1 All Pages Above Sign-In -->
<script type="text/javascript" src="http://apis.google.com/js/plusone.js"></script>
<script type="text/javascript" language="javascript">
x$("#xg_module_account").before("<div align=center id='custom_g1'></div>");
var g1_html = "<g:plusone></g:plusone><br>Don't forget to Like and +1 us!";
x$("#custom_g1").html(g1_html);
</script>
<!-- End G +1 -->

Where to find the Google Plus One Code if you need it:

http://www.google.com/webmasters/+1/button/

Enjoy!