Using this LotusScript agent example you can import people from Excel to Notes. Sample Excel file can be downloaded here.
Depending on the type of data and number of columns, speed of this method can be up to 100 times faster than reading cell-by-cell. It imports 100 person documents per second, and the most of this time is used on creating new Notes documents, not on getting data from Excel.

Sub Initialize 
'This agent imports records from excel to Notes. It uses Range method which makes it very fast. 
'Copyright Botstation (www.botstation.com) 

Dim session As New NotesSession 
Dim db As NotesDatabase 
Dim doc As NotesDocument 
Dim xlApp As Variant, xlsheet As Variant, xlwb As Variant, xlrange As Variant 
Dim filename As String, currentvalue As String 
Dim batchRows As Integer, batchColumns As Integer, totalColumns As Integer 
Dim x As Integer, y As Integer, startrow As Integer 
Dim curRow As Long, timer1 As Long, timer2 As Long 
Dim DataArray, fieldNames, hasData 

timer1=Timer 
filename="C:\people.xls" 
batchRows=200 'process 200 rows at a time 

Set db=session.CurrentDatabase 
Set xlApp = CreateObject("Excel.Application") 
xlApp.Visible = True 'set Excel program to run in foreground to see what is happening 
Set xlwb=xlApp.Workbooks.Open(filename) 
Set xlsheet =xlwb.Worksheets(1) 

Redim fieldNames(1 To 250) As String 

DataArray=xlsheet.Range("A1").Resize(batchRows, 250).Value 'get worksheet area of specified size 

For y=1 To 250 'we assume max 250 columns in the sheet 
currentvalue=Cstr(DataArray(1,y)) 
If currentvalue<>"" Then 'abort counting on empty column 
fieldNames(y)=currentvalue 'collect field names from the first row 
totalColumns=y 
Else 
y=250 
End If 
Next 

Redim Preserve fieldNames(1 To totalColumns) As String 

curRow=2 
hasData=True 
While hasData=True 'loop until we get to the end of Excel rows 
If curRow=2 Then startrow=2 Else startrow=1 
For x=startrow To batchRows 
curRow=curRow+1 
If Cstr(DataArray(x,1))+Cstr(DataArray(x,2))<>"" Then 'when 2 first columns are empty, we assume that it's the end of data 
Print Cstr(curRow-2) 
Set doc=New NotesDocument(db) 
doc.Form="Person" 
doc.Type = "Person" 
For y=1 To totalColumns 
currentvalue=Cstr(DataArray(x,y)) 
Call doc.ReplaceItemValue(fieldNames(y), currentvalue) 
Next 
doc.ShortName=doc.FirstName(0)+" "+doc.LastName(0) 
Call doc.save(True, False) 
Else 
hasData=False 
x=batchRows 
End If 
Next 
If hasData=True Then DataArray=xlsheet.Range("A"+Cstr(curRow)).Resize(batchRows, totalColumns).Value 'get worksheet area 
Wend 
timer2=Timer 
Call xlApp.Quit() 'close Excel program 
Msgbox "Done in "+Cstr(timer2-timer1)+" seconds" 
End Sub