Working Through Normalization (3NF) - database

Question

I've been planning this website for a while now and began putting it together a few weeks ago and I'd say that things were going extremely well until the other day I was introduced to normalization. It's taken me quite some time to get the hang of what it is and why it's needed but I think that I'm close to acheiving my overall goal now.
So the scenario is that I have a website where members can join and set up their own newspaper/blog and assign authors to it. The site primarily consists of a members_table, authors_table, newspapers_table and posts_table, which I've gone through and normalized to get:
Members
+----+-----------+----------+-----------------+----------+----------+------------+------------+
| ID | FIRSTNAME | SURNAME | EMAIL | USERNAME | PASSWORD | AVATAR | JOINED |
+----+-----------+----------+-----------------+----------+----------+------------+------------+
| 01 | Brian | Griffin | brian#gmail.com | briang | *** | hdhs.jpg | 2014-07-31 |
| 02 | Meg | Griffin | meg#gmail.com | megg | *** | | 2014-07-31 |
| 03 | Peter | Griffin | peter#gmail.com | peterg | *** | jaunsq.jpg | 2014-07-31 |
| 04 | Glen | Quagmire | glen#gmail.com | glen | *** | | 2014-07-31 |
+----+-----------+----------+-----------------+----------+----------+------------+------------+
Authors
+----+-----------+----------+-----------------+-------------------+---------+----------+---------+
| ID | FIRSTNAME | SURNAME | EMAIL | BIO ( REQUIRED ) | TWITTER | FACEBOOK | WEBSITE |
+----+-----------+----------+-----------------+-------------------+---------+----------+---------+
| 01 | Brian | Griffin | brian#gmail.com | About me... | URL | | URL |
| 02 | Meg | Griffin | meg#gmail.com | About me... | URL | | |
| 03 | Peter | Griffin | peter#gmail.com | About me... | | URL | URL |
| 04 | Glen | Quagmire | glen#gmail.com | About me... | URL | URL | |
+----+-----------+----------+-----------------+-------------------+---------+----------+---------+
** Should Socials Be Broken Down Here? If So, How?
Newspaper_Categories
+----+-------------------+
| ID | CATEGORY |
+----+-------------------+
| 01 | Lifestyle |
| 02 | Auto Mobiles |
| 03 | Entertainment |
| 04 | Food & Drink |
| 05 | Internet |
+----+-------------------+
Newspapers
+----+-----------------------+----------+---------+------------------+------------------+
| ID | NAME | CATEGORY | AVATAR | BIO ( REQUIRED ) | OWNER ( MEMBER ) |
+----+-----------------------+----------+---------+------------------+------------------+
| 01 | Spooner Street Weekly | 01 | 311.jpg | About Us... | 01 |
| 02 | A Dogs Life | 01 | | About Us... | 01 |
| 03 | In The Kitchen | 04 | js.jpg | About Us... | 02 |
+----+-----------------------+----------+---------+------------------+------------------+
Should Owner go Here or in a table named Newspaper_Owners
Socials
+----+-------------------+
| ID | TYPE |
+----+-------------------+
| 01 | Facebook |
| 02 | Twitter |
| 03 | Google |
| 04 | Flickr |
| 05 | Youtube |
+----+-------------------+
Newspaper_Socials
+----------+--------+------+
| NEWSAPER | SOCIAL | LINK |
+----------+--------+------+
| 01 | 01 | URL |
| 01 | 02 | URL |
| 01 | 05 | URL |
| 01 | 01 | URL |
| 02 | 02 | URL |
| 02 | 04 | URL |
| 03 | 01 | URL |
+----------+--------+------+
Post_Categories
+-------------------+--------------------+
| ID | NEWSPAPER_ID | CATEGORY |
+----+--------------+--------------------+
| 01 | 01 | Glens Girls |
| 02 | 01 | In The Clam |
| 03 | 01 | Peters Shenanigans |
| 04 | 02 | Martini Recipes |
| 05 | 03 | Housewife Tips |
+----+--------------+--------------------+
Posts
+----+----------+-------+---------+----------+------------+-------+
| ID | CATEGORY | TITLE | ARTICLE | FEATURED | ADDED | VIEWS |
+----+----------+-------+---------+----------+------------+-------+
| 01 | 01 | Title | Article | 0 | 2014-07-31 | 200 |
| 02 | 01 | Title | Article | 0 | 2014-07-31 | 220 |
| 03 | 03 | Title | Article | 1 | 2014-07-31 | 232 |
| 04 | 05 | Title | Article | 0 | 2014-07-31 | 143 |
| 05 | 05 | Title | Article | 1 | 2014-07-31 | 311 |
+----+----------+-------+---------+----------+------------+-------+
Post_Photos
+---------+-----+--------------+------+
| POST_ID | ALT | PHOTOGRAPHER | LINK |
+---------+-----+--------------+------+
| 01 | Alt | John Smith | URL |
| 02 | Alt | | |
| 03 | Alt | Mike Jones | |
| 05 | Alt | Adam West | URL |
+---------+-----+--------------+------+
Post_Keywords
+---------+---------+
| POST_ID | KEYWORD |
+---------+---------+
| 01 | Keyword |
| 01 | Keyword |
| 01 | Keyword |
| 01 | Keyword |
| 02 | Keyword |
| 02 | Keyword |
| 03 | Keyword |
| 03 | Keyword |
| 03 | Keyword |
+---------+---------+
If each post is only allowed 3 keywords, can these be added to the end of Posts table?
Author_Posts
+-----------+---------+
| AUTHOR_ID | POST_ID |
+-----------+---------+
| 01 | 01 |
| 01 | 02 |
| 01 | 03 |
| 02 | 04 |
| 03 | 05 |
+-----------+---------+
Could anyone please let me know if I'm on the right lines with this structure and give me some pointers on where Primary Keys and also Foreign Keys ??? should go?

Answer 1

"** Should Socials Be Broken Down Here? If So, How?"
Yes, you already have the socials table.
Add a new many to many table of Users to Socials