Need Links For Multiple Keyword Search Solutions Please

I have been informed that all my keyword search solutions are susceptible to SQL injection attacks.  Does anyone have links discussing basic ' multiple ' keyword search solutions?  I would think this is a very common routine (perhaps so much so than only newbies like myself do not know it).  I have read the posts about escaping ', doing replace " ' ", " '' ", using parameters and yet every multiple keyword solution I come up with is said to be injection prone.

Example: visitor enters:  Tom's antiques
into a TextBox control and the C# code behind securely generates the below call to the database.

SELECT L_Name, L_City, L_State, L_Display
FROM tblCompanies
WHERE L_Kwords LIKE '%' + 'Tom's' + '%' AND L_Kwords LIKE '%' + 'antiques' + '%' AND L_Display = 1
RETURN

I understand that concantenting string parts using an array and then passing the sewn together string to a stored procedure exposes it to injection.  I hope that my single keyword routine below is secure, if it is not then I am not understanding how parameterized SP are supposed to be constructed to protect against injection.string CompanyName;
CompanyName = TextBox1.Text;

PROCEDURE CoNameSearch
@CompanyName varchar(100)
AS
SELECT DISTINCT L_Name, L_Phone, L_City, L_State, L_Zip, L_Enabled, L_Display
FROM tblLinks
WHERE (L_Name LIKE @CompanyName + '%') AND L_Enabled = 1 AND L_Display = 1
ORDER BY L_Name
RETURN