Yes. 
 
To become a Mormon there is an established process. 
1 - Desire 
2 - Take lessons from fulltime missionaries 
3 - Agree to keep commandments of the Church (No smoking, drinking coffee/tea, no alcohol, no drugs, attend church regularly, no premarital sex, pay church tithing, etc. (This can mean a complete lifestyle change for some people, but the blessings that come with membership are priceless.) 
4 - Undergo a worthiness interview 
5 - Be baptized 
 
This might seem very difficult and demanding to do. However, the blessings of peace, happiness and true joy that come with priceless. Heavenly Father has promised that if we will keep His commandments that everything that is His - including eternal life living with Him - can become ours. How can one not want to do that for those kinds of eternal blessings?

Yes, baptism by one holding the proper priesthood authority (which is held only by the LDS Church) and confirmation is a requirement for membership.  
 
Without the ordinances of Baptism and Confirmation your cannot become a member of the Church because baptism it a requirement to unite with Christ and start your journey towards exaltation and the eternities.

Do you really need to do a worthinessinterview just to become a member? i thought that was only for temple visiting? 
 
and about paying tithing - not all members do that do they? And you dont get kicked out for not doing it?

Yes, there is an interview before being baptized. Being a member is a huge commitment. Baptism is a covenant between Heavenly Father and the individual. After being baptized there is a moral responsibility to keep the commitment with God. If one does not keep that commitment then they are in essence lying to God. So keeping the baptismal commitments is important. It is better to not be baptized and not make the commitments than to be baptized and not keep the commitments. The interview process is intended to ensure that the individual is sincere and willing to keep the commandments. It is also to prevent and protect the individual from making covenants with God that they cannot or don't intend to keep. 
 
Now once a person is baptized and then doesn't keep the commitments the Church generally is not going to come after that individual and punish them or kick them out. There is always room for repentance and forgiveness.

As Jett said yes you will have to be interviewed by a District leader (a young missionary in a leadership position in the stake) or the Mission President (in some incidents) depending on your personal situation and choices you have made before becoming an investigator.  
 
For example my wife at one time was in a same sex relationship years ago as a teenager, because of this she had to be interviewed by the Mission President because it can potentially disqualify someone for baptism if they have or are in a same sex relationship. Other things that require a Mission President to interview you is previous felonies, perviously excommunicated from the Church (and that requires approval from the First Presidency in SLC), etc  
 
This interview is about ensuring that you are ready for the responsibilities of baptism, that you are prepared to become a member of the body of Christ and take upon yourself the saviors name.  
 
This is a oath you are making with God to break it is to mock God and potentially blaspheme against the Holy Ghost which is the highest of sins. This interview is not about them prying into your life, it is simple questions and all you have to do is answer yes or no.  
 
The missionary or Mission President is not there to judge you it is an interview between you and Heavenly Father.  
 
As far as tithing goes, one of the covenants you make is to obey the commandments and one of God's commandments is to pay tithing. In fact you will be asked in your baptismal interview if you are willing to start paying tithes once you are baptized as well as obey the other commandments.  
 
Once a member if you choose to not pay tithes you cannot receive callings, the priesthood or advance in priesthood offices, or receive a Temple Recommend. Each year the member has a personal meeting with the Bishop called a "tithing settlement" here you get to declare if you are a full tithe payer and discuss any other matters that concern you spiritually.  
 
If you are not a full tithe payer you can expect the Bishop to invite you and challenge you to start paying tithes again in order to receive the blessings of being a full tithe payer.  
 
So ultimately if you do not believe in tithing you are not meant for the LDS Church, we are a tithing people and on top of that we generously give as able to other Church and non Church charities also.

But i read somewhere that far from all mormons pay tithe, not even all active ones?  
 
is it shameful to not pay tithe? is it obviuos if you dont, cause you wont get any callings, and then everyone will know?